Beginner Seasoned
Pick your zone and the dates re-calibrate.
The Guide Crops Vol. 003

Cucumber

in Zone 9, this week

Cucumber is an easy, fast warm-season vegetable grown for its crisp, immature fruit, picked while small and shiny. The plants grow as long vines or compact bushes and produce a lot in a short time. Like zucchini, you pick cucumbers often, every day or two, while they are still young; if you leave one on too long it gets fat, seedy, and yellow, and the plant stops making new ones. You can grow slicing cucumbers for fresh eating, small pickling cucumbers, or burpless and seedless types that are mild and gentle on the stomach. Cucumbers like warm soil, full sun, and steady watering. Letting them get too hot or too dry is what makes them taste bitter. Cucumber is a fast warm-season cucurbit grown for its tender, immature fruit, picked young while the skin is still glossy and the seeds are soft. Plants are vigorous and tendrilled, either long-vining or compact bush types, and they crop heavily over a short window once the heat arrives. Like summer squash, cucumber is a continuous-harvest crop: pick every day or two and the plant keeps setting, but let a fruit oversize and it turns seedy and yellow and the plant slows down. Growers choose among slicing types for fresh eating, blocky pickling types, and burpless or seedless (parthenocarpic) types bred to be mild and easy to digest. Cucumbers want warm soil, full sun, and steady, even moisture; uneven water and heat or drought stress are what turn the fruit bitter and misshapen.

Cucumber mature plant
Fig. 01 · Cucumber, mature Zone 9
Mature in
50-65d
from transplant
Sunlight
Full sun
6-10 hrs daily
Water
Moderate
1 inch / week
Spacing
12 to 18 in
between plants
Soil pH
6-6.5
slightly acidic
Today · in your zone

What's happening right now

October 21 · Zone 9 · Stage 01 · Germination

Off-season for cucumber in zone 9.

Seasoned
Microclimate · Zone 9a vs 9b

Your zone, at a finer grain

Zone 9 averages a last frost around March 1. Within Zone 9, the colder half (9a, winters down to 20°F) runs about a week later. The warmer half (9b, winters down to 25°F) runs about a week earlier. The plant app picks your subzone from your ZIP.

SubzoneLast springFirst fallGrowing daysWinter minFruits reliably
9aMar 8Nov 24~26120-25°FYes · two seasons
9bFeb 28Nov 30~27525-30°FYes · two seasons

Averages from 8 weather stations per subzone, drawn from NOAA 1991-2020 Climate Normals. Your actual frost date can vary by up to two weeks based on elevation, proximity to water, and local topography.

Source: NOAA 1991-2020 Climate Normals Methodology
Your climate region in Zone 9
The season at a glance

Planting calendar

In Zone 9, cucumber can be planted March through July. Start indoors Feb 15 - Mar 15. Harvest runs May through November.

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
plant
too cold
indoors
plant
plant
plant
plant
plant
too late
too late
too late
too early
too cold
harvest
harvest
harvest
harvest
harvest
harvest
harvest
harvest
indoors
plant out
harvest
Seasoned
Stagger your sowings

Succession planting

Cucumbers produce heavily for a few weeks, then slow down, so plant a few seeds now and a few more about three weeks later for a steadier supply. A second planting in summer is a smart backup, since pests and mildew often wear out the first plants by late summer.Cucumbers crop hard for a few weeks and then tire, so succession sowing keeps the supply steady instead of feast-then-famine. A first sowing after your last frost, then a second about three weeks later, spreads the harvest and keeps vigorous plants coming as the originals fade. The real payoff is late season: cucumber beetle, bacterial wilt, and powdery and downy mildew often take down the first planting by midsummer, so a replacement sown in early to midsummer, counting back from your first fall frost so it has time to mature, frequently outproduces the spring crop on cleaner, less stressed plants.

Every 3 weeks · sow a short new rowUp to 12 sowings a season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
sow
harvest
keep sowing
continuous harvest
The season, mapped

Seed to garden

The easiest way to grow cucumbers is to sow seeds right where they will grow, once the soil is warm (about 70°F). Plant a few seeds 1 inch deep in each spot and keep the strongest. Start seeds indoors only if your season is short, about three weeks before planting out, ideally in peat pots you can plant whole, and move them outside while they are still small.Because cucurbits resent root disturbance, direct sowing once the soil is reliably warm (at least 70°F at 2 inches; seed will not germinate below about 50°F) is the simplest, most reliable method, and direct-sown plants quickly catch up. Sow several seeds about 1 inch deep per hill or station and thin to the strongest. Start seeds indoors only to gain two to three weeks in a short season, sowing in peat pots three to four weeks before planting out and setting them out before they outgrow the pot.

  1. 01
    Sow indoors →
    Feb 15 - Mar 15
    Start about 3 weeks before your last frost
  2. 02
    Transplant out →
    Mar 15 - Jul 1
    After hardening off
  3. 03
    First harvest
    From May 10
    50-65 days from transplant
Start method
Both
Soil temp
70-95°F
Hardening off
7-10 days
If you started seedlings indoors, set them outside for a little longer each day over about a week so they get used to sun and wind. Be gentle with the roots when you plant, since cucumbers do not like having their roots disturbed. Peat pots you can plant whole help a lot.
From seed to fruit

The growing journey

Stage 01 · Germination
01
Germination
Days 3-10 · current stage
In warm soil, seeds sprout in about a week. Two seed leaves push up first. If the soil is cold, seeds rot instead of sprouting.Seeds sprout in about 4 to 10 days in warm soil (70 to 95°F is ideal); cold soil below about 50°F rots seed rather than germinating it.
Plant seeds 1 inch deep once the soil is warm. Keep the soil damp until they sprout. If several come up together, keep the strongest one.Sow 1 inch deep in warm soil. Keep evenly moist, not soggy. If you sowed several seeds per spot, thin to the strongest seedling once true leaves appear.
FROM PLANT · Wait for warm soil before sowing. Cucumber seeds rot in cold ground but sprout fast once it warms up.Soil temperature, not the calendar, governs cucumber germination. Wait until soil is at least 70°F at 2 inches; seed sown in cold ground below about 50°F rots before it sprouts.
02
Seedling
Days 10-21
After the first two rounded leaves, true leaves appear and the plant grows quickly. Watch for striped or spotted beetles chewing the young leaves.Cotyledons followed by the first true leaves; growth is fast once warm. Watch for cucumber beetles, which target young plants and can transmit bacterial wilt, to which cucumbers are very susceptible.
Keep an eye out for beetles on young plants. Set up a trellis now if your cucumbers climb. Water regularly and keep weeds down. A light row cover protects seedlings, but remove it once flowers form.Protect from cucumber beetles, with row cover if needed (remove it at flowering for pollination). Provide a trellis early if growing vining types. Keep evenly watered and free of weeds.
FROM PLANT · Protect young plants from beetles. A light cover helps, but take it off once flowers appear so bees can reach them.Cucumber beetles swarm young plants and spread bacterial wilt, which cucumbers catch easily. A floating row cover protects seedlings, but pull it off at flowering so bees can pollinate.
03
Established and vining
Days 21-35
The plant grows fast, sending out vines and curling tendrils that grab onto a trellis. This is when you feed it and make sure it has something to climb.Rapid leafy growth and lengthening vines that begin to throw tendrils and climb. This is the window to side-dress and to get the trellis in place before the vines sprawl, and to keep scouting for beetles and aphids.
Give the plant a light feeding of nitrogen now. Guide the vines onto their trellis. Add mulch to keep the soil evenly moist, which keeps the fruit from going bitter.Side-dress lightly with nitrogen as flowering nears. Train vines onto the trellis. Mulch to hold even moisture (which prevents bitterness). Keep scouting for cucumber beetles and aphids.
FROM PLANT · Give your cucumbers something to climb. Grown up a trellis, the fruit is straighter and cleaner and the plant gets less disease.Get the trellis in early. Cucumbers grown up a trellis make straighter fruit, stay cleaner and drier, suffer less disease, and are far easier to pick than sprawling vines.
FROM PLANT · Keep the soil evenly moist and mulched. Letting cucumbers dry out, then soaking them, is what makes them taste bitter.Even moisture is the anti-bitterness habit. Mulch and water steadily; the drought and heat swings that stress the plant are exactly what drive the bitter compound into the fruit, worst at the stem end and skin.
04
Flowering
Days 30-45
Yellow flowers open. The first flowers are usually male and fall off, which is normal. Female flowers have a tiny cucumber at their base.Yellow flowers open. Most cucumbers are monoecious, so male flowers (on thin stalks) usually open first and drop, which is normal; female flowers carry a tiny cucumber behind the bloom. Gynoecious and parthenocarpic types behave differently.
Let the bees do their work and do not spray the flowers. If tiny cucumbers turn yellow and shrivel, the flowers were not pollinated, and you can hand-pollinate with a small brush. Keep watering steadily.Encourage pollinators and avoid spraying open blooms, since fruit set depends on repeated bee visits. If small fruit yellow and shrivel, pollination is poor; hand-pollinate in the morning. Keep moisture steady now to avoid bitterness.
FROM PLANT · The first flowers often fall off without making cucumbers, that is normal. Real trouble is when tiny cucumbers turn yellow and shrivel, which means poor pollination.Early male flowers opening and dropping with no fruit is normal; females, each with a tiny cucumber behind the bloom, come a little later. Judge pollination by whether small fruit size up or yellow and shrivel.
FROM PLANT · If cucumbers are not forming, you can hand-pollinate. In the morning, pick a male flower, peel off the petals, and gently touch it to the center of a female flower.If set is poor in cool or pollinator-scarce conditions, hand-pollinate in the morning: pick a male flower, strip the petals, and dab pollen onto the center of each open female. Parthenocarpic types skip this entirely.
05
Harvest
Days 50-65
Shiny, firm cucumbers reaching the size you want. They grow fast, so they are ready before you expect.Glossy, firm fruit reaching pickable size for the type (2 to 4 inches for pickling, 6 to 8 for slicing), sizing up fast, often noticeably bigger day to day at peak.
Check every day or two and pick the cucumbers while they are firm and shiny. Cut the stem rather than pulling. Picking often keeps more coming, and remove any big yellow ones you missed.Pick every 1 to 2 days, cutting or clipping the stem. Harvest young for tenderness and to keep the plant producing; remove any oversized or yellowed fruit you missed, since they shut down new set and can turn bitter.
FROM PLANT · Pick cucumbers while firm and shiny and check every day or two, they grow fast. Picking often keeps more cucumbers coming.Pick young and pick often. At peak, fruit sizes up fast, so check every 1 to 2 days; harvesting promptly keeps the plant setting new fruit instead of slowing down, and young fruit is the most tender.
FROM PLANT · If a cucumber got big and yellow, pick it off anyway. Leaving over-ripe fruit on the plant makes it stop producing.Missed one and it turned yellow and seedy? Cut it off and compost it; leaving mature, seedy fruit on the vine tells the plant to stop setting, and over-ripe cucumbers turn bitter anyway.
06
End of season
Days 70-110
The plant slows down and the leaves may get powdery and white or yellow and spotted, or it wilts suddenly from disease. Frost kills it.Declining production, increasing powdery or downy mildew, or sudden wilting from bacterial wilt. The first frost kills the plant outright.
Pull out finished plants and clear them away at the end of the season. This helps prevent pests and disease next year. A second planting made in summer often keeps producing after the first one is done.Pull and remove spent vines rather than tilling them in, to cut overwintering pest and disease sites. A summer-sown succession often crops cleanly after the first planting fades to mildew or wilt.
FROM PLANT · At the end of the season, pull up old vines and clear them away. This cuts down on pests and disease next year.Pull spent vines and remove them rather than tilling them under, which buries overwintering beetles and disease residue. Clean beds now mean fewer pests and less angular leaf spot and anthracnose next season.
Beginner
Know your soil

Your soil

Identify yours

Not sure what soil you have? Grab a small handful of damp soil from your garden bed and squeeze it. If it crumbles apart easily, it's sandy. If it holds together but breaks when you poke it, it's loam (what most vegetables want). If it stays in a hard, slippery ball, it's clay.

What this crop wants

Plant cucumbers in rich, well-drained soil with plenty of compost mixed in. They grow fast and have shallow roots, so they like soil that stays evenly moist but never soggy. Many gardeners plant them on low hills or mounds, which warm up quicker and drain better, and growing them up a trellis keeps the fruit clean and straight. If your soil is heavy or stays wet, build up mounds or use raised beds so the roots do not sit in water.

What's a hill? A hill is a small group of seeds planted together in one spot. Once the seedlings come up, you remove the weaker ones and keep the strongest one to three plants. Snip or pinch off the extras instead of pulling them, so you don't disturb the roots of the plants you keep. Some guides raise the soil into a low mound for each hill so extra water drains away. Others treat a hill as just the group of plants, with no mound. The distance between hills is measured from one planted group to the next.

If your soil doesn't match

You have sandy soil

Mix 2-3 inches of compost into the top 6 inches of your bed before planting. Compost holds moisture (which sandy soil drains too fast) and adds the nutrients sandy soil tends to lack. Repeat each season. Compost breaks down over time.

You have clay soil

Mix 2-3 inches of compost AND a few inches of coarse sand or perlite into the top 6 inches of your bed. The compost feeds the plants; the sand breaks up the clay so air and water can move through. Don't add sand without compost. It can compact like concrete.

Containers and raised beds

If amending your soil sounds like too much work, or if your soil is heavy clay, full of rocks, or contaminated, build over it. A raised bed at least 12 inches deep filled with a 50/50 mix of compost and sandy loam gives you ideal growing soil with no battles. A 5-gallon container with quality potting mix does the same for one plant at a time. Both bypass your native soil entirely.

Learn more about your soil
The specs

Care guide

The numbers that matter, at a glance.

Sunlight
Full sun · 6-10 hrs/day
Water
moderate
Spacing
12 to 18 inches
Soil
loam
Days to maturity
50-65 days from transplant
Soil pH
6 to 6.5
Container OK?
Yes · 5+ gal pot
Germination temp
70-95°F
In a pot

Yes, 5 gallons and up

Cucumbers grow well in a container if you pick a compact or bush variety and give it a big enough pot, at least 5 gallons and 12 inches deep, with a small trellis or cage for the vines. Put it in full sun, keep it well watered (pots dry out fast, and dry cucumbers turn bitter), and feed it regularly. Water the soil, not the leaves, to help avoid mildew.Cucumbers are one of the better container cucurbits, especially compact or bush types such as Spacemaster, Bush Champion, Salad Bush, or Patio Snacker, and the parthenocarpic types that fruit without pollinators suit a balcony well. They still want a real pot: at least 5 gallons and 12 inches deep, larger is better, with a trellis or cage so the vines climb and the fruit hangs straight. Give it full sun, water at the base daily in heat (a dry pot makes bitter fruit), and feed regularly, since a small soil volume dries and depletes fast over the short, fast season. The container figures here follow general container-vegetable guidance; cucumber-specific container numbers are modeled.

Pot size
5 gallons and up; 10 gallons is comfortable
Drainage
Drainage holes are a must. Skip the gravel layer. If you use a saucer, empty it after watering. Cucumbers will not tolerate sitting in standing water, which invites root and stem rot.
Watering
Pots dry out much faster than garden beds. In summer a potted cucumber may need water every day, sometimes twice. Check daily and water until it drains from the bottom, since drying out makes cucumbers bitter.Containers dry far faster than beds, and a cucumber in a pot can need water once or even twice a day in summer heat. Check daily by feeling the top inch of mix, and water until it runs from the drainage holes; even moisture prevents the bitter, misshapen fruit that water swings cause.
Depth and shape
At least 12 inches deep. A container cucumber needs a deep, sturdy pot, at least 12 inches deep and 5 gallons or more, with a trellis or cage so the vines climb rather than sprawl over the rim. Trellising in a pot keeps the fruit straight and the foliage open against mildew. Choose compact, bush, or parthenocarpic types for containers rather than long sprawling vining kinds.
Self-watering pot
Yes. A self-watering container suits a potted cucumber well, smoothing the moisture swings this thirsty, bitterness-prone plant dislikes. Keep the reservoir topped up in heat, still water from below to keep foliage dry, and use a large enough planter that the roots are not constantly waterlogged.
Mix
Use a rich, free-draining peat- or coir-based potting mix, not garden soil, which compacts and drains poorly in a container. Blend in about a third compost plus a slow-release balanced fertilizer at planting. Because frequent watering flushes nutrients, plan to feed a container cucumber more regularly than one in the ground.
Feeding
Feed container cucumbers more often than in-ground ones, since steady watering leaches nutrients. After the slow-release charge at planting, add a balanced liquid feed every 2 to 3 weeks, keeping nitrogen moderate once fruit sets.
One to try

SpacemasterCompact bush slicer on short vines; one of the best choices for containers and small beds while still yielding full-size fruit.

4 more compact types

Bush Champion

Salad Bush

Patio Snacker

Pick a Bushel

Pot safety

Ask what your balcony or roof can carry

A balcony or roof can only hold so much weight. Before you set heavy pots there, ask a building architect what it can safely carry.Illinois Extension's guidance is to consult a building architect about weight limits before placing heavy pots on a balcony or rooftop garden. It gives no weight figure.

Never grow food in a container with anything toxic in it

Many kinds of containers can be used. Whatever you choose, keep anything toxic out of it, especially if you are growing food.Colorado State accepts nearly any container material but warns against using a container that holds toxic materials, especially for edible plants. Illinois adds that a vegetable container should be free of chemicals toxic to plants or people, and urges caution with treated lumber when growing food. If you cannot account for what a repurposed container once held, that alone is a reason to keep food out of it.

Secure hanging containers well

Fasten hanging baskets and window or rail boxes securely. Think about what is below them too, since they can drip on people or things underneath.Illinois Extension asks growers to secure hanging containers well and to think through the safety issues of hanging them. Placement matters too, since a hanging container can drip onto people or belongings below.

Soil chemistry

Soil pH for cucumber

Preferred
6 to 6.5
Tolerated
5.5 to 7

Cucumbers like soil that is slightly acidic to neutral, about pH 6.0 to 6.5, and most garden soil is already close. An inexpensive soil test tells you where you stand and whether you need to adjust it before planting.Cucumbers do best in slightly acidic to neutral soil, around pH 6.0 to 6.5. They still grow across a wider band, roughly 5.5 to 7.0, but uptake of some nutrients tightens as the soil turns alkaline. Test before planting and lime or add sulfur only on the test's advice rather than by guess.

Verified · 2 sources View
Steady hand on the hose

Watering

When & how much
Frequency
Give cucumbers about 1 inch of water a week, more when it is hot and dry. Water deeply rather than a little every day, and try to keep it steady so the fruit does not turn bitter.Aim for about 1 inch of water per week, more in heat or sandy soil, delivered deeply and less often rather than in light daily sprinkles. Even, steady moisture is what keeps cucumbers from turning bitter and misshapen.
Amount
About 1 inch of water a week is a good target, more while the plant is flowering and the cucumbers are growing. Cucumbers are mostly water, so do not let them dry out.Around 1 inch per week is the working range, leaning higher during flowering and fruit sizing and through hot, dry spells. Cucumbers are over 95 percent water and have shallow roots, so they show drought stress fast: uneven or inadequate water gives bitter, pinched, or curled fruit.
Method
Water the soil, not the leaves, using a soaker hose or watering wand at the base. Keeping the leaves dry helps prevent the leaf diseases cucumbers are prone to, and a layer of mulch keeps the soil evenly moist so the fruit stays sweet.Water at the base of the plant with drip or a soaker hose, keeping the foliage as dry as possible, since wet leaves invite powdery and downy mildew and angular leaf spot on an already disease-prone crop. A 2 to 3 inch mulch holds soil moisture even, which directly reduces bitterness, and keeps soil from splashing onto the leaves.
Signs of trouble
Too much water
If lower leaves yellow, the plant wilts even though the soil is wet, or the base gets soft and mushy, it is getting too much water or the soil drains poorly.Yellowing lower leaves, wilting even when the soil is wet, and soft, rotting stems at the base point to overwatering or poor drainage. Saturated soil invites root and fruit rot, especially on heavy ground.
Too little water
Some midday wilting in hot weather is normal and passes by evening. Leaves that stay wilted mean the plant is too dry, and drought while fruit is forming gives bitter, misshapen cucumbers.Midday wilting that recovers overnight is normal in heat, but leaves that stay limp and dull signal real drought. The clearest fruit-stage tell is bitter, pinched, or curled cucumbers, which trace directly to inadequate or uneven water during sizing.
Feeding rhythm

Feeding

Frequency
At planting, then side-dress once or twice
Type
balanced at planting, then nitrogen side-dress
When to start
Work into the bed before planting, then side-dress about a week after flowering begins and again 3 weeks later

Cucumbers grow fast and need a moderate amount of feeding, not a lot. Mix a balanced fertilizer or compost into the soil before planting, then feed with a little nitrogen about a week after the flowers start, and again a few weeks later if the plants look pale. Do not overdo the nitrogen, since too much makes leafy vines instead of cucumbers. Keep the plants evenly watered too, because feeding only helps a well-watered plant.Cucumbers are moderate feeders over a short, fast season. Work a balanced fertilizer or several inches of compost into the bed before planting, then side-dress with a little nitrogen about a week after flowering starts and again roughly three weeks later if the plants look pale. The main pitfall is too much nitrogen, which drives lush vines and leaf at the expense of fruit and draws aphids and disease. Pair feeding with steady, even moisture, because the nutrients only help a plant that is not also drought-stressed, and drought stress is what turns cucumbers bitter.

N · P · K = 10-10-10

Use a balanced fertilizer with equal numbers, like 10-10-10, at planting, then a little nitrogen once flowers appear. Avoid high-nitrogen lawn fertilizer.A balanced ratio such as 10-10-10 worked in at planting suits cucumbers, followed by a light nitrogen side-dress once they flower. Avoid high-nitrogen lawn-type fertilizers, which push foliage at the expense of fruit.

Try balanced 10-10-10 at planting, then a nitrogen source such as blood meal
Who grows well together

Companion planting

The most useful cucumber companions are flowers that bring in bees, since cucumbers need bee visits to set fruit, plants like radish and nasturtium that lure pest beetles away, and beans that feed the soil. Sunflowers or corn can act as a natural trellis. The one rule that really matters is to keep cucumbers away from other squash, melons, and pumpkins, which all share the same pests and diseases. Cucumber companions earn their place by drawing pests away, bringing in bees, or feeding the soil, rather than by crowding the bed. Give vining plants room or a trellis, and use companions as a border or light interplanting. The signature cucumber pest is the cucumber beetle, which also vectors bacterial wilt, so radish and nasturtium are traditionally interplanted to lure or deter beetles, and a row of sunflowers or corn can serve as a living trellis and windbreak. Because cucumbers are insect-pollinated, pollinator flowers like borage and dill keep bees working the blooms and improve fruit set. Beans fix nitrogen for the moderately hungry vines. Most of these pairings are traditional or mechanistic rather than trial-proven, and are labeled accordingly. The firmest rule is a rotation one: keep cucumbers away from other cucurbits, which share the whole pest and disease complex.

Other
Radish
Radishes are often planted among cucumbers to lure cucumber beetles, the cucumber's worst pest, away from the vines. They grow fast and are pulled before they crowd anything. A popular, low-risk traditional pairing.A long-standing trap and deterrent planting for cucumber beetles, the pest that also spreads bacterial wilt to highly susceptible cucumbers. Radishes are quick, cheap, and out of the bed before they compete, which makes them an easy interplant even though the beetle-reduction effect is traditional rather than trial-isolated. Traditional
Nasturtium
Nasturtiums lure cucumber beetles and aphids away from cucumbers and their flowers bring in bees. An easy, edible-flowered neighbor.Often planted near cucurbits as a trap and deterrent for cucumber beetles and aphids, and its flowers draw the bees cucumbers depend on for fruit set. Trap cropping is a documented principle, but the specific nasturtium-cucumber effect is not formally isolated, so treat it as a plausible aid. Well-grounded
Beans
Beans pull nitrogen from the air into the soil, which the fast-growing cucumber appreciates, and they do not share its pests. A good, traditional neighbor.Pole or bush beans fix nitrogen that benefits the moderately heavy-feeding cucumber, and they share none of the cucurbit pests. The nitrogen benefit largely reaches neighbors after the beans break down, so treat it as season-long soil-building rather than an instant feed, but the mechanism is sound. Well-grounded
Sunflower
A row of sunflowers gives cucumber vines something to climb and a bit of shade, and the blooms bring in bees. A practical, traditional support plant.Tall sunflowers can serve cucumbers as a living trellis and light windbreak, lifting the vines off the ground for cleaner, straighter fruit and better airflow, while their flowers recruit pollinators. The structural benefit is real and practical; the pairing is traditional rather than a measured yield effect. Traditional
Borage
Borage flowers are loved by bees, and cucumbers need bee visits to set fruit, so a few borage plants nearby can help with pollination. Mainly grown to bring in bees.A strong bee magnet whose flowers recruit the pollinators cucumber fruit set depends on, since the female flowers need repeated bee visits to size a fruit. Pollinator-habitat value is well grounded; the specific borage-cucumber pairing is traditional rather than trial-tested. Well-grounded
Herb
Dill
Dill flowers draw hoverflies, lacewings, and parasitic wasps that prey on aphids, and it is the classic kitchen partner for pickling cucumbers. The beneficial-insect draw is mechanistically sound; the specific cucumber pairing is traditional. Let some plants flower for the benefit. Well-grounded
interplant nearby
Keep apart from
Other cucurbits Keep cucumbers away from other squash, melons, and pumpkins. They all get the same pests and diseases, so planting them together makes those problems worse.Summer and winter squash, melon, and pumpkin share cucumber's whole pest and disease complex, including cucumber beetle with the bacterial wilt it spreads (to which cucumber is especially susceptible), squash bug, powdery and downy mildew, and angular leaf spot. Grouping them concentrates that pressure and lets problems build. A real epidemiology and rotation principle rather than a tested adjacency effect: spread cucurbits out and rotate them. Well-grounded
Potatoes Some gardeners keep potatoes and cucumbers apart, since both are hungry plants and potatoes can bring their own diseases. This is more tradition than a proven rule.A traditional caution that potatoes and cucumbers compete for the same nutrients and that potatoes can harbor blight and attract pests near the vines. There is no strong T1 mechanism for the specific pairing, so it persists mostly as garden lore. Traditional
Provenance tagged inline · see methodology for the labeling system Key
Harvest signals

When to pick

Pick cucumbers while they are young, firm, and shiny, before the skin dulls or yellows. Pickling cucumbers are usually picked small, around 2 to 4 inches, and slicing cucumbers around 6 to 8 inches, but the size is up to you. Cut or clip the stem instead of pulling, so you do not damage the vine. Check every day or two, because cucumbers grow fast and an over-ripe one turns yellow, seedy, and bitter, and leaving big fruit on the plant makes it stop producing. Pull off any you missed to keep more coming.Harvest cucumbers young and often, while the skin is glossy and firm and the seeds are still soft. Pick pickling types at about 2 to 4 inches, slicing types at about 6 to 8 inches, and burpless types per their variety length; the exact size is your preference, but earlier is more tender. Cut or clip the stem rather than pulling, to avoid tearing the brittle vine. At peak, check every 1 to 2 days, because a fruit left on the vine quickly turns yellow, seedy, and bitter, and a single oversized cucumber signals the plant to stop setting new ones. Remove any oversized or yellowed fruit you missed to keep the plant producing.

Verified · 2 sources View
Yield

What to expect

One cucumber plant produces a lot over the season, often a dozen or more slicing cucumbers. Two or three plants are plenty for fresh eating, while pickling takes more.A healthy plant yields heavily over its short season, commonly 10 or more slicing cucumbers per vine and many more from pickling types picked small, often 5 pounds or more in a long, warm climate. A few plants are plenty for fresh eating; a pickling project wants a block of them.

At its peak, a cucumber plant makes fruit fast. Pick every day or two, since picking often actually keeps more cucumbers coming.At peak in warm weather a plant sets fruit quickly, and cucumbers size up so fast that picking every 1 to 2 days is essential. Frequent harvest at this stage actually keeps the plant producing; leaving a mature, seedy fruit on the vine signals it to slow down or stop. Cucumber is one of the easier crops for beginners. The two things that catch people out are bitter fruit from letting the plants get dry, and plants suddenly wilting from a beetle-spread disease. Water steadily and watch for beetles early.Cucumber is forgiving and productive even for a first-time grower; the usual first-year surprises are bitterness from letting the plants dry out, and a sudden mid-season collapse from beetle-spread bacterial wilt. Steady water and early beetle control head off both.

What changes yield
Even moisture: steady water through fruit set drives sweet, well-formed fruit; drought and heat swings cause bitterness and misshapen cucumbers.Harvest frequency: picking young and often keeps a plant productive; letting fruit oversize and seed-up slows or stops new set.Pollination: poor pollination in cool or pollinator-scarce conditions causes small fruit to abort; parthenocarpic types are exempt.Pest and disease pressure: cucumber beetle and the bacterial wilt it vectors, plus powdery and downy mildew, commonly end the first planting.Season length and heat: warm seasons extend the productive window, but extreme heat stalls set and drives bitterness; a frost ends it.
Verified · 2 sources View
Pick your variety

Recommended varieties

Pick a cucumber for how you will use it. Slicing types like Marketmore 76 or Straight Eight are best for fresh eating, pickling types like Boston Pickling are best for pickles and picked small, and burpless or seedless types like Suyo Long or Diva are mild and easy to digest. If you only have a pot or a small bed, choose a compact bush type like Spacemaster. Disease-resistant varieties are worth seeking out, and milder, less-bitter kinds also attract fewer pest beetles.Choose a cucumber by use and space. For fresh eating, slicing types like Marketmore 76 (disease-tolerant and reliable) or Straight Eight are the standards; for pickles, the blocky, bumpy pickling types like Boston Pickling or National Pickling, picked small. Burpless and parthenocarpic types such as Suyo Long and Diva are bred to be mild, thin-skinned, and easy to digest, and the seedless parthenocarpic kinds set fruit without bees, which suits container and covered growing. Compact bush types like Spacemaster fit small beds and pots. Where disease pressure is high, lead with mildew- and wilt-tolerant varieties, and remember that less-bitter varieties also attract fewer cucumber beetles.

Marketmore 76
The standard open-pollinated slicing cucumber: long, dark-green, 8 to 9 inch fruit on disease-tolerant vines. Dependable and widely adapted, with resistance to several common diseases.
Straight Eight
Classic heirloom slicer with straight, smooth 8 inch fruit; an All-America Selections winner and a reliable garden standard.
Boston Pickling
Old open-pollinated pickling type with prolific, blocky, bumpy 3 to 6 inch fruit; excellent for pickles and seed-saveable.
National Pickling
Productive pickling cucumber bred for uniform small fruit; good for whole pickles when picked young.
Suyo Long
Asian burpless heirloom with long, ribbed, mild, thin-skinned fruit that is gentle on digestion; best trellised so the fruit hangs straight.
Diva
Award-winning parthenocarpic (seedless, burpless) slicer that sets fruit without pollination; tender, bitter-free, thin skin. Excellent under cover or in containers.
Lemon
Round, pale-yellow heirloom the size of a lemon; mild, never bitter, and very productive. A fun, easy garden novelty.
Spacemaster
Compact bush slicer on short vines; one of the best choices for containers and small beds while still yielding full-size fruit.
Off the vine

Storing your harvest

Room temp
Cucumbers do not keep long at room temperature, just a day or two. Use them soon or put them in the fridge, but not the coldest part.Cucumbers are tender and short-lived off the vine. At room temperature they keep only a day or two before softening, so use them quickly or refrigerate, with the caveat that cucumbers are chilling-sensitive and do not love a very cold fridge either.
Fridge
Keep cucumbers in the fridge for about a week, in the warmer crisper drawer rather than the coldest spot, since too-cold storage causes soft, pitted spots. Keep them away from apples and tomatoes, which make them go bad faster.Stored in the warmest part of the refrigerator, ideally around 45 to 50°F at high humidity, cucumbers keep about a week. They are chilling-sensitive below about 50°F, where prolonged cold causes pitting, water-soaked spots, and faster breakdown, so they store neither as long nor as cold as hardy vegetables. Keep them away from apples, tomatoes, and other ethylene producers, which hasten yellowing.
Freezer
Cucumbers do not freeze well, since they are mostly water and turn mushy. The best way to keep extra cucumbers is to make pickles.Cucumbers do not freeze well for fresh use, turning limp and watery because of their high water content. The practical way to keep a glut is to pickle it; freezing is only worth it for blended uses like soups or smoothies.
Verified · 2 sources View
When something goes wrong

Common problems

The cucumbers were bitterCucumbers tasted bitter
01 of 04
What happened The plant got stressed, usually by hot, dry, or uneven conditions, which makes cucumbers bitter. The bitterness sits mostly in the skin and the stem end.Stress, usually heat or uneven water, drove up the plant's natural bitter compound (cucurbitacin), which concentrates in the skin and at the stem end. Wide temperature swings, drought, and poor nutrition all bring it on, and some varieties are inherently more bitter than others. Next season Keep the plants evenly watered and mulched so they do not dry out, pick the cucumbers young, and try a burpless or non-bitter variety. Peeling and cutting off the stem end takes most of the bitterness out.Water steadily and mulch to keep soil moisture even, harvest before fruit oversizes, and grow non-bitter or burpless varieties. Peeling and cutting off the stem end removes most of the bitterness from a fruit you have already picked.
Tiny cucumbers turned yellow and shriveledSmall fruit yellowed and shriveled instead of sizing up
02 of 04
What happened The flower was not pollinated well, so the little cucumber died instead of growing. This often happens in cool or rainy weather, or when there are few bees.Poor pollination. Each female cucumber flower needs several bee visits to set; without enough pollen the young fruit aborts, yellowing and shriveling at the tip rather than sizing up. Common in cool, wet, or pollinator-scarce conditions and early in the season. Next season Grow some flowers nearby for the bees, and hand-pollinate early cucumbers if needed. It usually gets better as more flowers open and bees get active, or grow a seedless variety that does not need bees.Plant flowers to draw pollinators, avoid spraying open blooms, and hand-pollinate in the morning if early set is poor. Parthenocarpic varieties set fruit without pollination and sidestep the problem entirely.
Plant suddenly wilted and diedHealthy vine wilted and collapsed in midsummer
03 of 04
What happened Usually bacterial wilt, a disease cucumber beetles spread that cucumbers catch easily. It clogs the plant's water pipes so the vine wilts even when watered. Cut a wilted stem and pull it apart slowly to see sticky white strings.Most likely bacterial wilt, to which cucumbers are highly susceptible: cucumber beetles infected the plant, and the bacterium clogged its water-conducting tissue, collapsing a previously vigorous vine. The sap-string test confirms it. Squash bug feeding can cause similar wilting. Next season Keep cucumber beetles down, since they spread the disease there is no cure for. Cover young plants until they flower, and pull any plant that wilts and shows the sticky-string sign.Control cucumber beetles from the seedling stage with row cover until flowering, keep young plants vigorous, grow less-bitter varieties that draw fewer beetles, and remove infected plants promptly. There is no cure once a plant is infected.
Leaves got white and powdery and the plant died backLeaves turned white and powdery, then the plant faded early
04 of 04
What happened Powdery mildew, a white coating on the leaves, spread until the leaves died and the plant stopped early. Downy mildew, with yellow patches and fuzzy gray undersides, does similar damage in damp weather.Powdery mildew defoliated the plant ahead of schedule. The white fungal coating spread across the leaves until they browned and died, cutting the productive season short and exposing fruit to sunscald. Downy mildew (yellow vein-bounded blotches with gray underside) does the same in humid weather. Next season Pick resistant varieties, give plants room and a trellis for air flow, water the soil not the leaves, and treat early spots. A second planting helps too.Choose resistant varieties, space and trellis plants for airflow, water at the base, and treat at the first spots. A summer-sown succession can carry harvest past the worst of it.
The usual suspects

Pests & diseases

Pests
Cucumber beetles
P · 01
Symptoms Small yellow beetles with stripes or spots chew the leaves and flowers, especially on young plants. Worse, they spread bacterial wilt, a disease that makes cucumber vines suddenly wilt and die.Small yellow beetles, striped (three black stripes) or spotted (eleven black spots), chew young leaves, stems, flowers, and fruit. The bigger threat is indirect: both kinds transmit bacterial wilt, to which cucumbers are highly susceptible, so beetle feeding on seedlings can be followed weeks later by sudden, runaway vine wilt and collapse. Cause Cucumber beetles feed on the plants and carry the germ that causes bacterial wilt, infecting cucumbers as they chew. Young seedlings are most at risk, and cucumbers catch the wilt easily.Striped and spotted cucumber beetles feed on cucurbits and carry the bacterium that causes bacterial wilt in their gut, infecting plants as they feed. Cucumber is more susceptible to the wilt than squash or pumpkin, so even light beetle pressure on seedlings can be costly. Bitter-fruited varieties attract more beetles. Organic treatment Cover young plants with row cover (remove it when flowers open so bees can get in), pick the beetles off in the morning when they are slow, and use yellow sticky traps. Keeping the beetles down is the best way to avoid the wilt disease they spread.Protect seedlings with row cover removed at flowering, hand-pick beetles in the cool morning, and use yellow sticky traps to monitor and reduce numbers. Where bacterial wilt is a known problem, controlling the beetles is the only effective control of the disease, since there is no cure once a plant is infected. Prevention Cover seedlings until they flower, keep them growing strong, clear away weeds and old plants, and do not plant where squash-family crops grew last year.Exclude beetles from seedlings with row cover, keep young plants vigorous so they grow past the vulnerable stage, choose non-bitter varieties that attract fewer beetles, clear weeds and debris, and rotate away from where cucurbits grew. Aim control at the early-season colonizers that vector wilt.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Resistant varieties

    Bitter-fruited plants draw more beetles, so pick a variety described as non-bitter when you order seed. This one is settled before anything goes in the ground.Non-bitter cultivars attract fewer beetles, which lowers the early-season colonizing pressure that carries the wilt. A seed-order decision, and it does not replace exclusion at the seedling stage.

  2. Crop rotation

    Give cucumbers a bed where squash-family crops did not grow the year before. The beetles that matter most are the ones that arrive early in the season, since those are the ones carrying the wilt disease.Rotating out of ground that carried cucurbits reduces pressure from the early-season colonizers, which is the group worth aiming at because they are the wilt vectors.

  3. Garden sanitation

    Pull weeds and clear old plants from around the patch. It belongs in the standing prevention routine here rather than being a once-a-year job.Weed and debris removal around the planting is listed alongside rotation as prevention; it supports exclusion at the seedling stage rather than substituting for it.

  4. Floating row cover

    Cover seedlings with row cover, a light fabric laid over the plants, right from the start. Take it off once the flowers open so bees can reach them.Row cover over seedlings excludes colonizing adults through the stage when cucumber is most exposed to wilt infection; lift it at flowering for pollination and carry on scouting from there.

  5. Handpicking

    Pick beetles off by hand in the cool of the morning, when they are slow and easier to catch.Hand-collecting while adults are sluggish at first light keeps numbers down on a small planting, and it is worth most early in the season against the colonizers that vector wilt.

  6. Yellow sticky traps

    Yellow sticky traps, cards coated with glue, show you when beetles are about and catch some of them. Where the wilt disease is a known problem in your garden, keeping beetle numbers down is the way to avoid it, because an infected plant cannot be saved.Sticky traps serve both monitoring and some reduction in adult numbers. Where bacterial wilt is established, beetle suppression is the practical route to disease control, since there is no cure once a plant is infected.

No spray for this one. Prevention is the control.

Squash bug
P · 02
Symptoms Leaves get yellow spots, then brown and wilt, and you find clusters of shield-shaped gray-brown bugs and their bronze eggs on the undersides of leaves near the base of the plant.Leaves develop yellow specks that brown and wilt, and heavily fed vines wilt rapidly and turn brittle. Flat bronze to brick-red egg clusters appear on leaf undersides along the veins, and gray-brown adults and pale nymphs cluster near the crown and under debris. Cause Squash bugs pierce the leaves and stems and suck out the juices, which makes the vines wilt. They breed through the summer and hide in plant debris over winter.The squash bug, a true bug that feeds with piercing-sucking mouthparts on cucurbit foliage and stems, injecting saliva that wilts and browns the vines. Populations build through the season and are hardest to control once nymphs are large; the bugs overwinter as adults in garden debris. Organic treatment Pick the bugs off by hand and scrape off the egg clusters under the leaves. A board laid on the ground overnight draws them underneath, then lift it in the morning and destroy them. Treat the young bugs with insecticidal soap.Hand-pick adults, crush the egg masses on leaf undersides, and trap bugs by laying a board near the plants overnight, then lifting it in the morning and destroying the cluster underneath. Target young nymphs with insecticidal soap, since large nymphs and adults are tough to kill. Prevention Cover young plants until they flower, check under the leaves for eggs early in the season, and clean up old vines after harvest so the bugs have nowhere to overwinter.Use row cover on young plants until flowering, clean up vines and debris at season's end to cut overwintering sites, and rotate cucurbits. Scout leaf undersides for the bronze egg clusters from early in the season and act before nymphs mature.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Crop rotation

    Plant cucumbers somewhere other than the bed that grew squash-family crops last year.Cucurbit rotation is named together with end-of-season cleanup as the pair that lowers carryover from one season into the next.

  2. Garden sanitation

    Clear away old vines and plant debris after harvest. Squash bugs pass the winter as adults tucked into that debris, so taking it out removes their shelter.Post-harvest removal of vines and litter cuts overwintering sites for the adults, which is where the following season's population begins.

  3. Floating row cover

    Cover young plants with row cover, a light fabric laid over the bed, and leave it on until they flower. Then take it off so bees can pollinate.Row cover holds adults off through establishment; it comes off at flowering, so pair it with scouting from that point onward.

  4. Handpicking

    Pick the adults off by hand and scrape the bronze egg clusters off the undersides of the leaves. A board left flat on the ground overnight draws bugs underneath it, so lift it first thing in the morning and destroy what is there. Start checking leaf undersides early in the season, because the bugs get harder to deal with as they grow.Hand-collection plus crushing the egg masses laid along the veins is the core of it, and a board laid overnight concentrates adults and nymphs for morning removal. Scout undersides from early season, since control gets harder once nymphs are large.

  5. Insecticidal soap

    If you do spray, insecticidal soap works on the young bugs. The larger ones and the adults are tough to kill with it, so timing matters more than how much you use.Aim soap at small nymphs; large nymphs and adults are hard to kill, so a program that starts after the population has matured tends to disappoint.

The bottom rungs are products with label rules: timing, pollinators, and days to wait before harvest. Before you spray →

Aphids
P · 03
Symptoms Tiny soft insects gather on the undersides of leaves and on new growth, making leaves curl and turn yellow, often with a sticky film. They can also spread viruses to your cucumbers.Colonies of small soft-bodied insects, often melon aphids, cluster on leaf undersides and growing tips, causing leaves to curl, pucker, and yellow, with sticky honeydew and sooty mold following. Beyond direct feeding, melon aphids transmit cucumber mosaic and other viruses that mottle and distort the foliage and fruit. Cause Aphids are small insects that suck the plant's juices and multiply fast, especially on soft, over-fed growth. The sticky honeydew they leave behind grows black mold.Melon and other aphids suck sap and reproduce rapidly in warm weather, building up quickly on stressed or over-fertilized plants. The honeydew they excrete fosters sooty mold, and several aphid species spread cucumber mosaic virus. Organic treatment Blast them off with a strong spray of water and treat the undersides of the leaves with insecticidal soap, repeating every few days. Ladybugs and other helpful insects eat aphids, so welcome them.Knock colonies off with a strong jet of water and spray insecticidal soap or horticultural oil with thorough coverage of leaf undersides, repeating every few days. Conserve ladybugs, lacewings, and parasitic wasps, which usually bring aphids under control. Reflective or aluminum-foil mulch deters them from young plants. Prevention Do not over-fertilize with nitrogen, check the undersides of leaves regularly, and let helpful insects do their work instead of spraying everything.Avoid excess nitrogen, which drives the soft growth aphids favor, scout leaf undersides and growing tips, and support natural enemies rather than spraying broadly. Reflective mulch deters aphids from young plants.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Balanced nitrogen feeding

    Go easy on nitrogen fertilizer. Over-fed plants push soft new growth, and that is the growth aphids build up on fastest.Excess nitrogen drives the succulent growth melon aphid colonizes; restraint on feeding is a prevention habit, not a rescue step.

  2. Reflective mulch

    Reflective mulch, a silver or aluminum-foil sheet laid on the soil, puts aphids off young plants. Lay it while the plants are still small.Reflective or foil mulch deters colonizing aphids from small plants, which carries extra weight here because several aphid species move cucumber mosaic virus.

  3. Water spray

    Knock the colonies off with a strong jet of water from the hose, aimed at the undersides of the leaves where they gather.A forceful water jet dislodges colonies from leaf undersides and growing tips; treat it as the physical pass that comes before anything sprayed.

  4. Beneficial predators

    Ladybugs, lacewings and parasitic wasps eat aphids, and they usually bring a colony down on their own. Leave them alone and skip broad sprays that would take them out along with the aphids.Conserving lady beetles, lacewings and parasitoids is usually what ends an aphid run; spraying broadly removes that pressure, so support the natural enemies first.

  5. Insecticidal soap

    If the colonies keep building, treat with insecticidal soap and coat the undersides of the leaves where the aphids sit. Repeat every few days, since it only works where it actually lands.Soap is contact-only, so thorough coverage of leaf undersides decides the outcome; repeat every few days while colonies persist.

  6. Horticultural oil

    Horticultural oil is the other spray option, used the same way: cover the undersides well and repeat every few days.Oil is the alternative contact material at this rung, with the same coverage demand on leaf undersides and the same repeat interval.

The bottom rungs are products with label rules: timing, pollinators, and days to wait before harvest. Before you spray →

Spider mites
P · 04
Symptoms Tiny specks and a dusty, stippled look on the leaves, sometimes with fine webbing underneath, mostly in hot, dry weather. The leaves can dry out and die fast.Fine pale yellow and reddish-brown stippling on the upper leaf surface, often with faint webbing on the undersides, in hot, dry weather. Damage can develop very quickly: leaves bronze, dry, and drop, and a heavy infestation can kill a plant. Cause Spider mites are tiny relatives of spiders that suck the juice from leaf cells. They love hot, dry, dusty conditions and breed very fast.Two-spotted spider mites feed on the contents of individual leaf cells, and they multiply explosively in hot, dry, dusty conditions, especially on water-stressed plants. They are not insects, so many insecticides do not touch them. Organic treatment Spray the undersides of the leaves with a strong jet of water, and treat with insecticidal soap, repeating in about five days. Keeping the plants watered and the area free of dust helps a lot.Knock mites off with a strong spray of water to the leaf undersides, and treat with insecticidal soap or horticultural oil twice, about five days apart, covering the undersides well. Conserve predatory mites, ladybugs, and minute pirate bugs, which are the main natural controls. Prevention Keep cucumbers well watered, since dry, dusty plants attract mites. Rinse the leaves in hot weather and avoid spraying broad insecticides that kill the helpful bugs.Keep plants well watered and avoid drought stress, since mites flare on dry, dusty plants. Hose down foliage in hot spells, avoid broad-spectrum insecticides that kill the mites' natural enemies, and scout leaf undersides in hot weather.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Even watering

    Keep cucumbers watered steadily and do not let them go drought-stressed. Mites build up fastest on dry, dusty plants.Steady soil moisture removes the drought stress mites flare on; on a hot, dusty site it separates a slow build from an explosive one.

  2. Water spray

    Spray the undersides of the leaves with a strong jet of water. It knocks mites off and washes dust away, and it is worth doing through hot spells rather than waiting for damage.Hosing leaf undersides dislodges mites and suppresses the dust that favors them; run it as a routine in hot weather, not only after stippling shows.

  3. Beneficial predators

    Predatory mites, ladybugs and minute pirate bugs are the main things holding spider mites in check, so avoid broad insecticides that would kill them off. Mites are not insects anyway, so many insecticides do not touch them.Predatory mites, lady beetles and minute pirate bugs carry most of the control, and broad-spectrum insecticides remove them. Spider mites are not insects, so much of that spraying would miss the target while costing the natural enemies.

  4. Insecticidal soap

    Insecticidal soap works if you coat the undersides of the leaves well. Plan on a second treatment about five days after the first.Soap is contact-only against a pest sitting on leaf undersides, so coverage there governs the result; the repeat at roughly five days is part of the treatment rather than an optional follow-up.

  5. Horticultural oil

    Horticultural oil is the other option, used the same way: cover the leaf undersides and repeat in about five days.Oil sits at the same rung on the same twice-at-five-days interval, and coverage of the undersides again decides it.

The bottom rungs are products with label rules: timing, pollinators, and days to wait before harvest. Before you spray →

Diseases
Powdery mildew
D · 01
Symptoms A white, powdery coating spreads over the leaves until they turn yellow and brown and die. The plant fades early and the cucumbers may not size up well.White, powdery patches appear on the upper and lower leaf surfaces and stems, spreading until leaves yellow, brown, and die back ahead of schedule. Early defoliation cuts the season short, reduces yield, and exposes fruit to sunscald. Cause A fungus that spreads on warm days with high humidity, especially where plants are crowded and air does not move well. It does not need wet leaves to take hold.Powdery mildew fungi that thrive between about 50 and 90°F in dry weather with high humidity, and unlike most leaf diseases they do not need leaf wetness to infect. Crowded plantings, poor airflow, and shade worsen it, and it is one of the most common late-season cucumber diseases. Organic treatment Treat early, at the first white spots, with a labeled fungicide like sulfur or horticultural oil, and remove badly affected leaves. Water the soil, not the leaves. Once it covers the plant it is hard to stop.Treat at the first spots, before it spreads, with a labeled fungicide such as sulfur, potassium bicarbonate, neem, or horticultural oil, covering both leaf surfaces, and remove the worst leaves. Avoid overhead watering. Once it is widespread, control is mostly damage limitation. Prevention Pick resistant varieties, give plants plenty of room so air moves between them, plant in full sun, and water at the base. Start checking in midsummer and act at the first white spots.Choose resistant varieties, space plants generously for airflow, plant in full sun, and avoid excess nitrogen and overhead watering. Scout from midsummer and treat at the first sign, since prevention and early action beat rescue.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Resistant varieties

    Start by picking a variety sold as resistant to powdery mildew. It is the easiest way to stay ahead of one of the most common late-season cucumber diseases.Resistant cultivars are the highest-leverage choice for a disease that shows up routinely late in the cucumber season and is hard to reverse once it is widespread.

  2. Airflow and spacing

    Give plants generous spacing so air moves between them, and put the patch in full sun. Crowding and shade both make this worse.Spacing and site are set at planting: crowded, shaded, poorly ventilated plantings favor it, and these fungi work in humid air without needing wet leaves to infect.

  3. Water at the base

    Put water on the ground at the base of the plants instead of over the top of the foliage.Base watering is specified here even though this fungus can infect without leaf wetness, so treat it as a standing habit rather than a mildew-specific mechanism.

  4. Garden sanitation

    Take off the worst-affected leaves as you find them.Pulling the heaviest-infected leaves reduces what is left to spread from; once the fungus is established this is damage limitation rather than a fix.

  5. Sulfur

    Start checking plants in midsummer and treat at the first white spots with a labeled fungicide such as sulfur, covering both the top and the underside of the leaves. Once the coating is over the whole plant it is hard to stop, so acting early is the whole point.Sulfur applied at first symptom, with both leaf surfaces covered, is the window that pays, and scouting from midsummer is what makes that timing possible. Once it is general across the canopy the effort shifts to damage limitation.

The bottom rungs are products with label rules: timing, pollinators, and days to wait before harvest. Before you spray →

Downy mildew
D · 02
Symptoms Yellow patches show on top of the leaves, often boxed in by the veins, with fuzzy gray growth underneath in damp weather. The spots brown and spread until the leaves die. Cucumbers catch it easily.Angular yellow blotches, bounded by the leaf veins, appear on the upper leaf surface, with a grayish or purplish fuzzy growth on the underside in humid weather. Spots brown and run together, and severe infection rapidly defoliates the vines. Cucumber is one of the most susceptible cucurbits. Cause A mold-like disease that spreads in wet, humid weather and needs wet leaves to infect. It can move through a planting very quickly, and cucumbers are especially prone to it.A fungus-like water mold (Pseudoperonospora cubensis) that spreads on wind-borne spores and needs leaf wetness and humidity to infect, so it flares in wet, humid spells and dewy conditions. It moves fast once established and is favored by crowding and prolonged leaf wetness. Organic treatment Open up the planting so leaves dry faster, remove the worst leaves, and use a labeled fungicide when wet weather sets in. Do not water over the leaves.Improve airflow, let foliage dry, remove badly affected leaves, and apply a labeled fungicide such as copper or chlorothalonil, covering leaf undersides, when conditions favor the disease. Avoid overhead irrigation, which keeps leaves wet and feeds the infection. Prevention Give plants room so air moves between them, water at the base, and watch closely in humid weather. Choose resistant varieties if downy mildew is common where you live.Space for airflow, water at the soil line rather than overhead, choose resistant varieties where available, and avoid working among wet vines. Scout closely in humid weather, when the disease can appear and spread quickly.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Resistant varieties

    If downy mildew turns up most years where you live, choose a resistant variety when one is available for what you want to grow.Cucumber sits among the most susceptible cucurbits, so resistant cultivars, where they exist, are the prevention lever worth seeking out at seed-buying time.

  2. Airflow and spacing

    Space plants so air moves between them and the leaves dry off quickly. This disease needs wet leaves to get started.Spacing shortens leaf-wetness periods, and wetness is the infection requirement; crowding plus prolonged wetness is what lets it run through a planting.

  3. Water at the base

    Water at the base of the plants. Watering over the top keeps the leaves wet, which is exactly what this disease needs.Overhead irrigation sustains the leaf wetness infection depends on, so watering at the soil line removes that input.

  4. Garden sanitation

    Pull off the badly affected leaves as the spots spread, and do it once the foliage has dried rather than while the vines are wet.Remove the worst leaves when foliage is dry rather than moving through wet vines. It trims what is on hand to spread, though wind-borne spores mean it will not hold the disease on its own.

  5. Copper fungicide

    When wet, humid weather sets in, a labeled copper fungicide can help, sprayed to cover the leaf undersides where the fuzzy growth shows. Put it on as the weather turns rather than after the spots have taken over.Copper applied when conditions favor infection, with leaf undersides covered, is protective; it works alongside airflow and dry foliage rather than in place of them.

  6. Chlorothalonil Rescue only

    If downy mildew keeps moving after the copper, chlorothalonil is the other fungicide this crop's guidance names for it. Cover the undersides of the leaves, since that is the surface it has to protect, and start when the weather turns to what the disease likes rather than once the leaves are already covered. Read this one's warnings before you decide: it is the heaviest thing in this guide, and stopping at the copper is a real choice.The second material named for this disease alongside copper, and applied on the same terms: undersides covered, begun as conditions turn favorable rather than after lesions are established. Protectant only, so it defends clean tissue and does nothing for what is already infected. Weigh the method's own cautions, which are the heaviest carried by anything in this catalog, against stopping one rung lower.

The bottom rungs are products with label rules: timing, pollinators, and days to wait before harvest. Before you spray →

Bacterial wilt
D · 03
Symptoms Vines wilt and die even though the soil is wet. If you cut a wilted stem and pull the two ends apart slowly, infected sap stretches into sticky white strings. Cucumbers get this disease easily.Individual leaves, then whole vines, wilt and collapse even though the soil is moist, often spreading until the plant dies. A field test helps confirm it: cut a wilted stem and slowly draw the cut ends apart, and infected sap pulls into thin, sticky white strands. Cucumber is especially susceptible. Cause A germ spread by cucumber beetles as they feed. It blocks the plant's water pipes, so the vine wilts even when watered. Cucumbers are very prone to it.A bacterium (Erwinia tracheiphila) spread by striped and spotted cucumber beetles, which carry it in their gut and infect plants as they feed. It clogs the water-conducting tissue, so the plant wilts despite adequate water. Cucumber and muskmelon are far more susceptible than squash and pumpkin. Organic treatment There is no cure once a plant has it, so pull and destroy infected plants. The real fix is keeping cucumber beetles down, since they spread it.There is no cure once a plant is infected; remove and destroy wilting plants to limit spread. Control is really beetle control, so management aims at keeping cucumber beetle numbers down, especially early in the season. Prevention Keep cucumber beetles under control, since they spread the disease. Cover young plants until they flower, and pull any plant that wilts and tests positive with the sap-string check.Manage cucumber beetles from seedling stage with row cover removed at flowering, keep young plants vigorous, choose less-bitter varieties that attract fewer beetles, and remove infected plants promptly. Controlling the beetle vector is the only effective control of the disease.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Garden sanitation

    There is no cure once a plant is infected, so pull out wilting plants and destroy them instead of leaving them in the bed. To check first: cut a wilted stem and draw the two cut ends slowly apart, and infected sap pulls into sticky white strings.Prompt removal and destruction of wilting vines is the only in-season action available, since an infected plant cannot be recovered; confirm with the stem-sap strand test before pulling.

  2. Floating row cover

    The real control is keeping cucumber beetles off the plants, since they carry the germ and infect cucumbers as they chew. Cover seedlings with row cover, a light fabric laid over the bed, and take it off when the flowers open so bees can get in.Excluding the beetle vector from the seedling stage is the effective control of the disease itself, because the beetles are what introduce the bacterium as they feed. The cover comes off at flowering, so beetle management has to continue past that point.

No spray for this one. Prevention is the control.

Angular leaf spot
D · 04
Symptoms Small water-soaked spots on the leaves, bounded by the veins so they look angular. In damp weather a white crust forms underneath, and the dried spots tear out, leaving ragged holes in the leaves.Small, water-soaked spots on the leaves expand until they are boxed in by the larger veins, giving them an angular shape. In humid weather a milky bacterial ooze dries to a thin white crust on the underside, and as the spots dry they tear away, leaving ragged holes. Fruit can develop small, sunken, water-soaked spots. Cause A bacterial disease carried on seed and spread by splashing water and wet hands. It is worst in warm, rainy weather and survives the winter in old plant debris.A seedborne bacterium (Pseudomonas syringae pv. lachrymans) that is spread by splashing water, rain, and handling wet plants, and overwinters in crop residue. It is most damaging in warm, wet weather, roughly 75 to 82°F with frequent rain. Organic treatment There is no cure, so remove the worst leaves, stay out of the patch when the plants are wet, and use a labeled copper spray early if it is spreading. Water the soil, not the leaves.There is no rescue spray that cures it; remove badly affected leaves, avoid working among wet plants, and apply a labeled copper bactericide at the first sign to slow spread. Water at the base to keep foliage dry. Prevention Buy clean seed and resistant varieties, water at the base, stay out of the patch when it is wet, and clean up old vines at the end of the season. Move cucumbers to a new spot each year.Plant certified disease-free seed and resistant varieties, do not work among wet vines, water at the soil line rather than overhead, rotate cucurbits on a three to four year cycle, and remove crop debris after harvest.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Clean planting stock

    Buy certified disease-free seed. This one travels on the seed itself, so a clean start matters more here than it does with most leaf diseases.The pathogen is seedborne, so certified clean seed closes the introduction route; skip it and every later step is working against a source you planted.

  2. Resistant varieties

    Pick a resistant variety alongside the clean seed.Variety resistance is named together with clean seed as the pair that sets your starting risk, before any in-season step is available.

  3. Crop rotation

    Move cucumbers to a new spot and keep squash-family crops out of that bed for three to four years. The bacteria survive the winter in old plant debris.A three to four year cucurbit rotation outlasts survival in crop residue, which is the carryover route left once seed is clean.

  4. Water at the base

    Water the soil at the base of the plants. This disease moves in splashing water, so watering overhead spreads it around the patch.Splash dispersal is the in-season spread mechanism, so base watering removes the irrigation half of it; rain will still do the same work.

  5. Garden sanitation

    Take off the worst leaves and clear out old vines at the end of the season. Wait until the plants are dry before you go in, because handling wet vines moves the bacteria around on your hands and clothes.Do leaf removal and post-harvest residue cleanup on dry foliage; handling wet plants is a listed spread route alongside splash, and residue is where the bacterium overwinters. There is no rescue spray that cures this one.

  6. Copper fungicide

    A labeled copper spray used at the first sign can slow the spread. It does not cure the disease, so treat it as a brake while the other steps do the work.Copper at first symptom slows progress rather than curing; bring it in when spots are appearing and the cultural steps are not holding.

The bottom rungs are products with label rules: timing, pollinators, and days to wait before harvest. Before you spray →

Anthracnose
D · 05
Symptoms Brown or black spots on the leaves that can fall out and leave holes, and dark, sunken, circular spots on the cucumbers themselves that rot in wet weather.Yellowish or water-soaked leaf spots that turn brown to black and may drop out, giving a shot-hole look, plus elongated tan lesions on stems and dark, circular, sunken cankers on the fruit. In wet weather the fruit cankers ooze a pinkish spore mass and rot. Cause A fungus that spreads in warm, rainy weather and splashing water, and survives on old plant debris and infected seed.A fungus (Colletotrichum orbiculare) that needs several days of rainy, warm weather to infect and spreads in splashing water. It survives on old cucurbit residue and on infected seed. Organic treatment Remove infected leaves and fruit, water at the base, and use a labeled fungicide in long wet spells. Do not save seed from sick plants.Remove infected leaves and fruit, avoid overhead watering, and apply a labeled fungicide such as chlorothalonil preventatively in wet spells. Do not save seed from infected plants. Prevention Start with clean seed, rotate cucumbers to a new spot for a few years, clean up old vines after harvest, and water the soil rather than the leaves.Use disease-free seed and resistant varieties, rotate out of cucurbits for three years, remove and destroy old vines and residue after harvest, and water at the soil line to keep foliage dry.
The control ladder

The ladder troubleshoots from the gentlest solution to the strongest. Start with the gentlest option and only move on when and if it doesn't work.

  1. Clean planting stock

    Start with disease-free seed, and do not save seed off plants that had it. The fungus can ride infected seed into the next season.Seed transmission is one of the two carryover routes, so clean purchased seed plus a rule against saving seed from infected plants closes it.

  2. Resistant varieties

    Choose a resistant variety when you are buying seed.Variety resistance is listed with clean seed as the pre-season pair, and it is the leverage you have before the wet spells that drive infection arrive.

  3. Crop rotation

    Keep squash-family crops out of that bed for three years. The fungus survives on old cucurbit residue.A three year rotation out of cucurbits outlasts survival on residue, the carryover route besides seed.

  4. Water at the base

    Water the soil rather than the foliage. This fungus spreads in splashing water, so keeping the leaves dry limits how far it travels.Splashing water is the dispersal mechanism, so base irrigation and drier foliage cut spread; the several days of warm, rainy weather infection needs are outside your control.

  5. Garden sanitation

    Remove infected leaves and fruit as you find them, and destroy the old vines and debris after harvest.In-season removal of lesioned leaves and sunken, cankered fruit plus destruction of post-harvest residue addresses both current spread and overwintering on debris.

  6. Chlorothalonil Rescue only

    This is the only spray this crop's guidance names for anthracnose, and it is meant preventively: it goes on ahead of a wet spell rather than after spots show. Notice the gap below it. There is no gentler spray listed for this disease on this crop, so the step under this one is the cleanup, and declining to go further is a reasonable place to stop rather than a rung skipped. Read this method's warnings before you take it, because it is a long way up from the step below.The only material this crop's guidance names for anthracnose, specified preventively in wet spells, which is when the infection periods fall. The escalation runs straight from sanitation to a conventional here because the source offers nothing between the two, so the jump is a property of the evidence rather than a gap in the ladder. Declining it leaves the cultural program as the whole of the control, which is what the source describes for a home crop.

The bottom rungs are products with label rules: timing, pollinators, and days to wait before harvest. Before you spray →

Verified · 2 sources View
Seasoned
Where to plant next year

Crop rotation

Try not to grow cucumbers or their relatives in the same spot more than once every 3 years or so. Moving them around the garden each year helps avoid a buildup of pests and disease. Clean up old vines at the end of the season too.Rotate cucurbits on a 3 year cycle, and a 3 to 4 year break where angular leaf spot or anthracnose has been a problem, since both persist on residue. The point is to break the buildup of cucumber beetle, beetle-vectored wilt, and soilborne and seedborne disease. Clear and remove spent vines at season's end rather than tilling them in, which removes overwintering pest and disease sites and makes rotation more effective.

Family
Cucurbitaceae
Years between
3 years
in the same bed
Avoid following
Do not plant cucumbers where you grew squash, melons, pumpkins, or other cucumbers in the last few years. They get the same pests and diseases, which build up in the soil.Avoid planting cucumbers where another cucurbit grew in the last few years, including squash, melon, pumpkin, and other cucumbers. They share cucumber beetle with the bacterial wilt it spreads, squash bug, powdery and downy mildew, angular leaf spot, and anthracnose, all of which build up in the soil and on debris.
Plant after
Legumes such as beans and peas, sweet corn, leafy greens, or alliums like onions and garlic make good preceding crops, since they do not share the cucurbit pest and disease complex, and a legume leaves nitrogen behind for the moderately hungry cucumber.
Verified · 2 sources View
In the app · pre-launch

When plant taps you on the shoulder

The plant app sends a timely reminder at every critical moment of your cucumber season. The wording adjusts to whichever you pick: beginner or seasoned. Here are three you'll see in Zone 9.

p
plant
Time to watch for beetles Start scouting for cucumber beetles
Your young cucumbers are up. Check for small striped or spotted yellow beetles, which spread a wilt disease cucumbers catch easily, and cover the plants until they flower. Your cucumber seedlings are up, which is when cucumber beetles colonize and can infect highly susceptible plants with bacterial wilt. Scout daily and protect young plants with row cover until flowering.
p
plant
Plant a second cucumber now Sow your backup cucumbers
Now is a good time to plant a second cucumber as a backup. Pests and mildew often wear out the first plants by late summer, so a fresh planting keeps cucumbers coming. Time to sow a succession planting. A fresh sowing now, counted back from your first fall frost, often outproduces the spring crop on cleaner plants once beetles and mildew wear the first planting down.
p
plant
Check for ready cucumbers Check your cucumbers, they size up fast
Your cucumbers are making fruit. Check every day or two and pick them while firm and shiny, they grow fast. Your cucumbers are fruiting. At peak they size up fast, so check every 1 to 2 days and pick young. Frequent picking keeps the plant producing; a fruit left to oversize turns bitter and stops new set.
Get personalized alerts.

plant sends the right notification at exactly the right moment, for your zone, your weather, your crops. Founding members lock the rate forever.

Back the Kickstarter →
Ask the gardener

Common questions

Got a question we missed?

We're building this guide with real growers. Got a question we missed? Ask here. We read every one and add the best answers right to this page.

Grown this before?

Share a tip

Learned something the hard way? Pass it on. Real growers' tips make this guide better for the next person, and we credit you by name when yours goes live.

Seasoned
Spot something wrong?

Report a problem

If you've grown this crop and you see a date, a temperature, a companion claim, or a recommendation that doesn't match your experience, tell us. Real growers' corrections make this guide better for the next person.

How we built this guide

Methodology & sources

Every date, temperature, spacing, and recommendation on this page is sourced from university cooperative extension publications, peer-reviewed agricultural research, NOAA climate data, and direct extension calendars. Where claims are softer (traditional gardening wisdom not formally documented), we say so.

Research-backed Documented in cooperative extension publications or peer-reviewed research
Well-grounded A known agronomic principle, but not formally tested for this specific pair
Traditional Time-tested gardening wisdom, limited formal research support
Last reviewed
June 29, 2026
Data version
crops_data_final · v1.0 · schema 2.9
Sources cited on this page
16 publications
Verified entries
Companion-planting claims tagged inline · zone dates verified against 5+ extensions
See all sources cited on this page
  • University of Minnesota Extension umn_ext
  • University of Maryland Extension umd_ext
  • Cornell Cooperative Extension cornell_ext
  • Iowa State University Extension iastate_ext
  • Michigan State University Extension msu_ext
  • NC State Extension ncsu_ext
  • Penn State Extension psu_ext
  • U. of Illinois Urbana-Champaign Extension uiuc_ext
  • UC Davis Postharvest Center ucd_postharvest
  • Texas A&M AgriLife Extension tamu_agrilife
  • Virginia Cooperative Extension 426-331 vce_426_331
  • Piedmont Master Gardeners piedmont_mg
  • UGA Vegetable Garden Calendar uga_calendar
  • Clemson Home & Garden Information Center clemson_hgic
  • UC IPM Statewide IPM Program uc_ipm
  • NOAA 1991-2020 Climate Normals noaa_normals

Read the full methodology →

Spot a data point that doesn't match your experience? Submit a correction; accepted corrections earn full author credit on the page.

Growing notes, weekly.

Zone-aware seasonal nudges, what's worth planting now, and the occasional recipe from the harvest. No spam, ever.

Vol. 003 · Cucumber · plant.lifestyle

Glossary