Calibrated to Pick your zone and the dates re-calibrate.

The Guide Flowers Vol. 003

Calendula

in Zone 11, this week

Calendula, also called pot marigold, is an easy, cheerful flower for cool weather. It is not the same plant as the marigolds you may know (those are a different plant called Tagetes). Calendula handles light frost, blooms in the cool parts of the year, spring and fall, and right through winter in mild-winter areas, but it fades and stops flowering in hot summer weather. The gold and orange petals are edible and add color to food, and the flowers have long been used in skin creams and salves. Plant the seeds in cool weather, snip off faded blooms to get more, and it will often drop seed and come back on its own. Calendula (Calendula officinalis), commonly called pot marigold, is a cool-season, frost-tolerant annual in the Asteraceae family, native to the Mediterranean. Despite the name, it is not a true marigold (those are Tagetes); it is a separate genus grown for single to double daisy-form blooms in gold, orange, yellow, and apricot. It thrives in the cool shoulders of the year, blooming almost continuously from spring or fall sowings, and through winter in mild and Mediterranean zones, but it languishes and stops flowering once sustained summer heat above roughly 85°F sets in. Plants tolerate frost to about 25°F, self-seed readily, and rebloom well with deadheading. The petals are edible, lending a saffron-like color to food, and calendula has a long traditional use in skin salves.

Fig. 01 · Calendula, mature Zone 11

Mature in

45-60d

from transplant

Sunlight

Full sun to part shade

6-8 hrs daily

Water

Moderate

Spacing

8-12"

between plants

Soil pH

6-7

slightly acidic

Today · in your zone

What's happening right now

July 24 · Zone 11 · Stage 01 · Germination

Off-season for calendula in zone 11.

Your climate region in Zone 11

The season at a glance

Planting calendar

In Zone 11, calendula can be planted October through January, skipping the summer heat.

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

plant

too late

too hot

plant

bloom

indoors

plant out

bloom

Keep them blooming Deadhead spent blooms through the bloom window to keep new flowers coming.

Seasoned

Stagger your sowings

Succession planting

For flowers all through the cool season, sow a new small batch of seeds every 3 to 4 weeks in spring and again in late summer and fall (and through winter where winters are mild). Stop during the hot months: calendula does not do well sown into summer heat.Sow successively every 3 to 4 weeks through the cool windows, early spring and again late summer into fall, and through winter in mild and Mediterranean zones, to keep fresh, vigorous plants in bloom. There IS a heat pause: stop sowing through the hot months, since calendula germinates and blooms poorly in summer heat.

Every 3 weeks · sow a short new rowUp to 12 sowings a seasonToo hot to sow midsummer

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

sow

bloom

keep sowing

too hot

continuous bloom

The season, mapped

Seed to garden

The easiest way is to sow calendula seeds straight into cool garden soil (about 60°F), a quarter to half an inch deep, and cover them well because the seeds need darkness to sprout. They come up in one to two weeks. For a head start, sow indoors about 6 to 8 weeks before your last frost and move the young plants outside. You can pinch the tops once to make plants bushier.Calendula direct-sows readily into cool soil (about 60°F) at 1/4 to 1/2 in depth; cover the seed, because light inhibits germination. It germinates in 1 to 2 weeks and is the simplest method in the cool shoulders. To gain time in short-season areas, start indoors about 6 to 8 weeks before the last frost and transplant; calendula resents heavy root disturbance, so use cells or pots and transplant while young. Pinch once when young for bushier plants.

01

Sow outside

Oct 1 - Jan 31

Start method

Both

Soil temp

60-70°F

From seed to fruit

The growing journey

Stage 01 · Germination

Germination

Days 5-14 · current stage

The first little leaves push up through the soil in one to two weeks. The seeds need to be covered to sprout.Seed leaves (cotyledons) emerge from cool soil within roughly 1 to 2 weeks; the seeds need darkness, so they must be covered.

Keep the soil damp and cover the seeds well, because they need darkness to sprout.Keep soil cool and evenly moist near 60°F; cover seed about 1/4 to 1/2 in, since light inhibits germination.

FROM PLANT · Cover the seeds well, about a quarter to half an inch deep, because calendula needs darkness to sprout. In cool soil they come up in one to two weeks.Cover calendula seed about 1/4 to 1/2 in; light inhibits germination, so darkness and cool soil near 60°F are the triggers. Seedlings emerge in 1 to 2 weeks.

FROM PLANT · Plant calendula in cool weather, not summer heat. Sow in early spring and again in late summer or fall (and in winter where winters are mild). Hot soil keeps the seeds from sprouting well.Sow into cool soil, the way you would spinach: direct-sow in early spring and again in late summer or fall, and through winter in mild and Mediterranean zones. Calendula germinates poorly in hot soil.

Seedling

Days 14-26

Real leaves appear and the little plant starts to settle in.First true leaves develop on a low rosette; the plant is small and establishing roots in cool weather.

Space plants about 8 to 12 inches apart and water the soil, not the leaves.Thin or space plants to 8 to 12 in; water at the base and watch for slugs and aphids in damp weather.

FROM PLANT · Once seedlings have a few real leaves, space them about 8 to 12 inches apart. Room for air to move helps prevent the white mildew.Thin or space seedlings to 8 to 12 in once they have a few true leaves; generous spacing for airflow is the main cultural defense against powdery mildew.

FROM PLANT · Watch young calendula for aphids and slugs in cool, damp weather; aphids really like calendula. Spray them off with water or use insecticidal soap.Scout young calendula for aphids and slugs in cool, damp weather; calendula is an aphid magnet. Hose off aphids or use insecticidal soap, and the beneficials the flowers draw will help later.

Established / vegetative

Days 24-40

The plant gets bigger and bushier with more leaves.Plant grows bushier with several leaf sets and begins branching; a quick grower in cool conditions.

Pinch off the top once to make the plant branch out, and go easy on fertilizer.Pinch the growing tip once for bushier plants; keep nitrogen modest so plants flower rather than run to leaf.

FROM PLANT · Pinch off the top once when the plant is young to make it bushier with more flowers. Go easy on fertilizer so you get flowers, not just leaves.Pinch the growing tip once on young plants to force branching and more flowering stems; keep nitrogen modest so plants flower rather than run to soft, mildew-prone foliage.

FROM PLANT · Keep calendula in sun with room around it and water the soil, not the leaves. Dry, airy plants are what keep the white mildew away, especially as it warms up.Maintain full sun and airflow and water at the base; dry, well-spaced foliage is what keeps powdery mildew in check, sharpest as the weather warms.

Budding

Days 35-52

Flower buds start to form at the tops of the stems.Flower buds form at stem tips; stems lengthen toward bloom, roughly 6 to 8 weeks from sowing.

Keep the soil evenly moist and start checking for aphids and white powdery mildew.Keep moisture even at bud point; begin scouting for aphids and, in warm humid weather, powdery mildew.

FROM PLANT · Keep the soil evenly moist when the first flower buds appear, but not soggy. Too dry means smaller flowers; too wet rots the plant.Keep moisture even as the first buds form; drought stress at bud point reduces flower size and count, but never let the soil stay wet, which rots crowns and feeds mildew.

FROM PLANT · As buds form, check for aphids on them and for white powdery mildew in warm, damp weather. Catching crowding and wet leaves early keeps both down.Scout for aphids on buds and for powdery mildew as warm, humid weather arrives; addressing crowding and overhead wetness early limits both.

Flowering

Days 45-60

Flowers open, about six to eight weeks after planting, and keep coming through the cool weather.Blooms open and continue; first bloom is roughly 6 to 8 weeks from sowing and continues through the cool season until hard frost or summer heat ends it.

Snip off faded flowers (or cut some for a vase, or pick petals to eat) to get more blooms.Deadhead spent blooms, or cut for the vase, to sustain bloom; harvest petals on a dry morning; water at the base.

FROM PLANT · Snip off faded flowers back to the next leaves (or cut fresh ones for a vase) to get more blooms through the cool weather. Leave a few at the end to drop seed for next time.Deadhead spent blooms back to the next leaf, or cut for the vase, to redirect energy from seed set into new flowers and sustain bloom through the cool season. Leave a few late heads to self-sow.

FROM PLANT · Pick petals from fully open flowers on a dry morning, using only unsprayed plants. Pull off the colorful petals and skip the bitter green base. Use them fresh on food for color, or dry them and keep in a jar for tea or homemade skin salve.Harvest petals on a dry morning from fully open, unsprayed flowers; pull the ray petals and discard the bitter green base. Use fresh as a saffron-like color, or dry on a screen out of sun and store airtight for tea, color, and traditional salve.

Seed saving (optional)

Days 65-95

A few flowers left on the plant dry out and form curved seeds you can save.Selected heads left on the plant dry to brown and set viable, curved seed; most calendula come reasonably true from seed.

Let a few flowers dry out fully on the plant before collecting their seeds. Calendula also reseeds itself.Leave chosen heads to dry fully before collecting; open-pollinated types come fairly true, and calendula self-sows readily.

FROM PLANT · To save seeds, leave a few flowers on the plant until they dry and turn brown, then collect the curved seeds. Calendula usually grows true from saved seed and also reseeds itself.To save seed, leave some heads to dry fully to brown before collecting the curved seeds; most calendula are open-pollinated and come reasonably true, and the plant self-sows freely.

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

Calendula is easygoing and grows in most ordinary garden soil as long as water drains away and does not pool. Moderately fertile, well-drained soil is ideal. It handles poorer soil too, but soggy ground rots the roots, so pick a spot that drains well and add a little compost if your soil is thin.

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 to part shade · 6-8 hrs/day

Water

moderate

Spacing

8-12 inches

Soil

loam, sandy loam

Days to maturity

45-60 days from transplant

Soil pH

6 to 7

Container OK?

Yes · 1+ gal pot

Germination temp

60-70°F

Soil chemistry

Soil pH for calendula

Preferred

6 to 7

Tolerated

5.5 to 7.5

Calendula is not picky about soil pH (how acidic or alkaline the soil is). A normal garden range around 6.0 to 7.0 is ideal, and you usually do not need to change anything.Calendula performs best across roughly 6.0 to 7.0 and tolerates a little outside that range. It is broadly adaptable to soil chemistry, so pH adjustment is rarely warranted; focus on drainage and moderate fertility instead.

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Steady hand on the hose

Watering

When & how much

Frequency

Keep the soil damp while seeds sprout and plants get going, then water regularly but do not keep it soggy. Calendula likes steady moisture in cool weather, but wet, mucky soil rots it. Water the soil, not the leaves.Keep soil evenly moist through germination and establishment, then water regularly but moderately; calendula prefers consistent moisture in cool weather but resents waterlogged soil, which rots roots and feeds disease. Water at the base and avoid wetting foliage to limit powdery mildew.

Amount

Calendula likes about one inch of water a week, counting rain. Water the soil deeply a couple of times a week rather than a little every day, and let the top of the soil dry a bit between waterings. It needs less in cool winter weather.Aim for roughly one inch of water per week from rain plus irrigation during active growth, applied at the base; let the surface dry slightly between waterings. Needs are lower in the cool, short days of winter bloom and higher as plants size up in spring.

Method

Water the ground around the plant, not the leaves. A soaker hose or watering can at the base works best, because dry leaves resist mildew. If leaves do get wet, water in the morning so they dry by midday.Water at the base with drip or a soaker hose and keep foliage dry; overhead wetting in the cool, humid conditions calendula favors invites powdery mildew and crown rot. If you must use a sprinkler, water in the morning so leaves dry fast.

Signs of trouble

Too much water

If lower leaves turn yellow, the plant wilts even though the soil is wet, or the base looks soft and mushy, you are likely overwatering or the soil drains poorly.Yellowing lower leaves, wilting despite wet soil, and soft, rotting stems or crowns signal overwatering or poor drainage; persistently wet foliage also raises powdery-mildew and damping-off pressure.

Too little water

Calendula that is too dry wilts in the warmth of the day, looks dull, and makes smaller flowers. It is thirstiest right after planting and when the first buds form.Wilting in the warmth of the day, dulling leaf color, and smaller flowers at bud point indicate underwatering, most critically during establishment and at first bloom; chronic drought hastens the heat-driven decline of the planting.

Feeding rhythm

Feeding

Frequency

light

Type

Balanced or low-nitrogen

When to start

At planting, then sparingly

Calendula does not need much feeding. Mix a little balanced fertilizer or compost into the soil before planting and that is usually plenty. Too much fertilizer, especially the high-nitrogen kind, gives you leaves instead of flowers and more pest and mildew trouble.Calendula is a light feeder and needs little supplemental fertilizer. A modest balanced dose worked into the soil at planting is usually enough. Excess nitrogen pushes soft, leafy growth that flowers poorly and is more prone to powdery mildew and aphids, so favor a balanced or slightly lower-nitrogen feed and skip routine feeding once established.

N · P · K = 10-10-10

The three numbers on fertilizer (N-P-K) are nitrogen, phosphorus, and potassium. For calendula, pick a balanced one like 10-10-10 rather than a high first-number (nitrogen) lawn feed, which gives leaves instead of flowers.A balanced ratio such as 10-10-10 worked in at planting suits calendula better than a high-nitrogen lawn-type feed, which favors foliage over flowers.

Flower care

Deadheading calendula

Flower form

single to double, daisy-form, in gold, orange, yellow, and apricot

Deadheading means snipping off flowers once they fade. Do it regularly: cut the old bloom back to the next set of leaves and the plant makes more flowers instead of going to seed. Cutting flowers for a vase or picking petals does the same job. Leave a few flowers at the end of the season to drop seed, and calendula often comes back on its own. Pinch young plants once to make them bushier.Deadhead spent blooms back to the next leaf through the cool season to redirect energy from seed set into new flowers and sustain bloom; cutting for the vase or harvesting petals serves the same function. Calendula reblooms well with regular deadheading and slows when it is allowed to set seed, though it self-sows freely if you leave the last heads. Pinch young plants once to force branching and more flowering stems.

Who grows well together

Companion planting

Calendula is a classic, cheerful companion plant grown to help the rest of the garden. Unlike true marigolds (Tagetes), it is not a proven soil-nematode fighter, so do not expect that from it. What it does well is bring in bees and helpful insects like hoverflies and ladybugs, whose young eat aphids. Gardeners also plant it as a trap or decoy because aphids love it, drawing them off nearby crops, and it traditionally goes near vegetables for color and pollinators. There is no plant you must keep it away from; just give it sun and room, and remember it likes cool weather, so pair it with other cool-season crops. Calendula's companion value is pollinator and beneficial-insect support, not the nematode suppression documented for true marigolds (Tagetes); pot marigold is a separate genus and should not be assumed to share that effect. Its open, nectar-rich flowers draw bees, hoverflies, lacewings, and ladybugs whose larvae prey on aphids, so it earns its place as an insectary edge. Because aphids are strongly attracted to calendula, it is also used traditionally as a trap or banker plant to pull aphids off a main crop, a tactic with a plausible mechanism but limited formal trialing. As a cool-season annual it pairs naturally with other cool-season vegetables and flowers. There is no biologically antagonistic companion to avoid; site for sun and airflow.

Other

Bees and beneficial insects (insectary planting)

Calendula flowers for a long time and bring in bees and helpful bugs like ladybugs and hoverflies. Their young eat aphids, so a calendula edge or border helps the whole garden.Calendula's best-grounded companion function. Its open, long-blooming flowers recruit bees and aphid-predators (hoverflies, lacewings, ladybugs, parasitic wasps), supporting biological control nearby. Plant it as an insectary edge or interplant for predator support and color; this is a habitat benefit, not a documented pest-repellent effect. Well-grounded

Aphid-prone crops (as a trap or decoy plant)

Aphids love calendula, so some gardeners plant it near aphid-prone crops to lure the aphids onto the calendula instead. Watch the calendula and wash off or remove the aphids there.A traditional trap-crop pairing. Calendula is strongly attractive to aphids, so it is planted near aphid-prone crops as a decoy to concentrate aphids on the calendula, where they can be hosed off, removed, or left for predators. The mechanism (a preferred host pulling pests off the cash crop) is sound, but the protective effect is traditional practice, not formally trialed; monitor and manage the aphids on the trap so it does not become a reservoir. Traditional

Cool-season vegetables (lettuce, brassicas, peas)

Calendula grows in the same cool weather as lettuce, cabbage-family crops, and peas, so it makes an easy, colorful companion in the cool-season garden, adding flowers and pollinators without crowding them for food.A cool-season habitat pairing. Calendula occupies the same cool shoulders as lettuce, brassicas, and peas, adding pollinator and beneficial-insect habitat and color with low nutrient competition. The benefit is ecosystem support and aphid-predator recruitment; keep it to edges and ends of rows so it does not shade lower crops. Traditional

Provenance tagged inline · see methodology for the labeling system Key

Cutting for the vase

When to cut

Calendula is mostly for cool-season color, pollinators, and its edible petals. Cut flowers for a vase when fully open and the stem feels firm, in the morning into clean water. To eat the petals, pick fully open, unsprayed flowers on a dry morning, pull off the colorful petals, and skip the bitter green base. Snip off faded flowers through the season to keep more coming.Calendula is grown for garden color, pollinators, cutting, edible petals, and traditional herbal use. Cut blooms for the vase when flowers are fully open and the stem is firm, in the cool of the morning into clean water; expect several days of vase life. Harvest petals from fully open, unsprayed flowers on a dry morning, pulling the rays and discarding the bitter green base. Deadhead spent blooms through the cool season to sustain flowering.

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Bloom yield

What to expect

One calendula gives you lots of flowers over the cool season. Short types make many small blooms; tall types make fewer, bigger flowers on long stems good for cutting or for picking petals. Keep snipping faded flowers and more keep coming until it gets too hot or freezes hard.A single calendula blooms generously over the cool season, carrying a steady succession of 2 to 3 in daisy flowers; dwarf types make many smaller blooms for color and edging, while tall strains give fewer, longer-stemmed flowers for cutting and petal harvest. Deadheading or cutting sustains production until heat or hard frost ends it.

Calendula flowers the same season you plant it, about six to eight weeks after sowing. There is no waiting year, and it often drops seed and comes back on its own.Calendula blooms the first season from seed, roughly 6 to 8 weeks after sowing, so there is no establishment year; a cool-season sowing flowers through the cool months and self-sows for the next.

What changes yield

Season fit: calendula yields most in cool weather and stops blooming in sustained heat above about 85°F, so a long cool shoulder or mild winter maximizes total bloom.Type: dwarf types yield many small flowers for color and edging; tall strains yield fewer, longer-stemmed blooms for cutting and petals.Deadheading and cutting cadence: regular deadheading or cutting sustains bloom; neglected plants set seed and slow.Pinching: pinching young plants once produces more, sturdier flowering stems.Spacing and airflow: adequate spacing limits powdery mildew and sustains a longer productive life.

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Pick your variety

Recommended varieties

Pick the type for your spot. Tall kinds like Pacific Beauty and Indian Prince give long stems good for cutting; short, early kinds like Bon Bon and Calypso are great for the front of a bed or in pots. If you want calendula for skin salves or tea, look for Resina, a type grown for that. All calendula have edible petals, and the simpler, more open flowers are best for bees. Most come true from seed you save yourself.Choose by height and purpose. Tall strains such as Pacific Beauty and Indian Prince give long, cuttable stems for the vase and the back of a bed; dwarf, early types such as Bon Bon and Calypso suit edging, the front of a border, and containers. For herbal and salve use, growers favor high-resin selections such as Resina (often grown as single or semi-double flowers that are easy to pick). Most calendula are open-pollinated and come reasonably true from saved seed, and all are edible-petaled; single and semi-double forms serve pollinators best.

Pacific Beauty

tall, long-stemmed mix in cream to deep orange; a classic cut-flower strain

Bon Bon

dwarf, very early, compact double blooms for beds, edging, and containers

Resina

pale lemon, high-resin selection favored for herbal and salve use

Indian Prince

deep orange with a bronze-red petal reverse, tall and weather-tough

Snow Princess / Ivory Princess

soft cream to pale yellow doubles

Calypso

compact, dark-centered doubles in orange and yellow

Greenheart Orange

novelty orange with a green center

In the vase

Vase life

Calendula is a flower for the garden and the vase, not food to store like vegetables. To make cut flowers last, cut them in the morning and put them in clean water. The orange and gold petals are edible: pull them off the flower, skip the bitter green base, and sprinkle them fresh on food for color (a cheap stand-in for saffron), or dry them on a screen and keep them in a sealed jar for tea or homemade salve. Only eat flowers that have not been sprayed.Calendula is grown for bloom, a pollinator draw, an edible petal garnish, and traditional herbal use, so the refrigerate and freeze fields do not apply as for produce. For cut flowers, cut in the cool of the morning into clean water and expect several days of vase life. The ray petals are edible: pull them from the flower head, discard the bitter green base, and use fresh as a slightly bitter, saffron-like color for soups, rice, salads, and butters, or dry them on a screen out of direct sun and store airtight for tea, color, and salve-making. Use only unsprayed flowers.

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When something goes wrong

Common problems

Calendula quit flowering when it got hotPlants stopped blooming and got leggy in summer heat

01 of 06

What happened Calendula does not like heat. When summer warmed up, it stopped flowering and got tall and tired. That is just how this cool-season plant behaves.Calendula is a cool-season annual; sustained heat above about 85°F stops flowering and makes plants leggy and mildew-prone. This is normal, not a mistake. Next season Plant calendula in the cool parts of the year, spring and fall, and skip the hot months. In mild-winter areas, grow it right through winter.Grow calendula in the cool shoulders and mild winters; sow in early spring and again in fall, and treat summer as its off-season in hot regions.

Leaves got a white powdery coatingWhite powdery film on the leaves (powdery mildew)

02 of 06

What happened A white powdery mildew covered the leaves, usually because plants were crowded or shaded, the air was humid, or it was warming up.Powdery mildew took hold, favored by warm, humid, crowded, shaded conditions, and it worsens as the season warms past calendula's cool comfort range. Next season Give plants more room and sun, water the soil instead of the leaves, and pick off bad leaves. Growing in cooler weather helps most.Space plants for airflow, grow in full sun, water at the base, and remove affected leaves; grow in the cooler part of the season.

Young plants fell over, or the base rottedSeedlings collapsed or plants rotted at the base

03 of 06

What happened A rot at the base, from cold, soggy soil, killed the plants. Overwatering or poor drainage is the usual cause.Damping-off and root or stem rot struck plants in cold, wet, poorly drained soil; calendula rots if kept saturated in cool weather. Next season Plant in soil that drains well, do not keep it soggy, and give plants room for air.Sow into well-drained soil, do not overwater, and ensure airflow; avoid sowing into cold waterlogged ground.

A hard freeze killed the plantsPlants killed by a hard freeze

04 of 06

What happened Calendula handles light frost but not a hard, deep freeze. A hard freeze ended the plants.Calendula tolerates light frost to about 25°F but a hard freeze below that damages or kills it; in cold zones the first hard freeze ends the season. Next season In cold areas, know the first hard freeze ends calendula. In mild-winter areas it keeps going through winter.Expect cold-zone plantings to end at the first hard freeze; in mild zones calendula blooms through the winter.

Tiny bugs and sticky leaves (aphids)Sticky, curled growth crawling with aphids

05 of 06

What happened Aphids, which love calendula, covered the new growth and buds and left everything sticky.Aphids colonized the plant; calendula is strongly attractive to them, clustering on buds and new growth, leaving honeydew and sometimes vectoring virus. Next season Spray aphids off with water or use insecticidal soap. The flowers also bring in ladybugs that eat them.Hose off aphids or use insecticidal soap, encourage the beneficials the flowers draw, and use calendula deliberately as a trap plant if helpful.

Few or no seeds sproutedSeeds failed to come up

06 of 06

What happened Calendula seeds did not sprout, usually because they were not covered (they need darkness) or the soil was too warm.Usual causes are uncovered seed (light inhibits germination) or hot soil; calendula germinates best covered, in cool soil near 60°F. Next season Cover the seeds well so they are in the dark, plant in cool soil, and keep it damp until they sprout.Cover seed 1/4 to 1/2 in, sow into cool soil near 60°F, and keep evenly moist during emergence.

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The usual suspects

Pests & diseases

Pests

Aphids

P · 01

Whiteflies

P · 02

Slugs and snails

P · 03

Diseases

Powdery mildew

D · 01

Damping-off and root or stem rot

D · 02

Cucumber mosaic and aster yellows

D · 03

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Seasoned

Where to plant next year

Crop rotation

Rotating calendula is not as important as it is for vegetables, but it helps. Plant it in a different spot each year if you can, and clean up old, diseased leaves at the end of the season. Calendula reseeds itself, so you will often get new plants popping up nearby on their own.Rotation matters less for a fast cool-season ornamental annual than for heavy-feeding vegetables, but moving calendula to a fresh bed and clearing infected debris limits carryover of powdery mildew and aphid-vectored virus. Because it readily self-seeds, expect volunteers, and thin or relocate them to keep airflow.

Family

Asteraceae

Years between

1 years

in the same bed

Avoid following

Calendula is in the daisy family (Asteraceae). If it had a lot of mildew or virus, do not plant it, or other daisy-family flowers, in the same spot the very next season, and clean up the old leaves. Note that calendula drops seed and often comes back on its own.As an aster-family (Asteraceae) annual, avoid following calendula immediately with other susceptible asters where powdery mildew or aster yellows built up; rotate the bed to an unrelated family for a season if disease was heavy, and clear infected debris at season end. Calendula self-sows freely, so volunteers may appear regardless of rotation.

Plant after

legumesleafy greens

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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 calendula season. The wording adjusts to whichever you pick: beginner or seasoned. Here are three you'll see in Zone 11.

plant

2 weeks before last frost

Time to plant calendula

You can plant calendula seeds in cool weather, even a couple of weeks before your last frost, since it handles light frost. Sow about a quarter inch deep and cover them well.

plant

Seedling arrives

Space out your seedlings

Space your calendula plants about 8 to 12 inches apart now so air can move between them.

plant

Flowering arrives

Time to deadhead and cut

Your first flowers are opening. Snip off faded ones (or cut some for a vase, or pick petals to eat) to keep more blooms coming.

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Seasoned

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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 30, 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

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