Calendula, also called pot marigold, is one of the oldest medicinal and edible flowers in the garden: its bright orange and yellow blooms have been used for skin creams, teas and cooking for centuries, and it is also simply a cheerful, easy flower that blooms for months. It is not a true marigold, though it looks like one, and it grows in much the same easy way.
Calendula is a hardy annual, so it can be sown in autumn in mild zones or in spring in cold ones, and it flowers best in cool weather — it keeps blooming through spring and autumn and often through a mild winter. It self-seeds freely, so once you have grown it, you will usually have it forever, and it is a wonderful companion plant in the vegetable garden, drawing in pollinators and beneficial insects.
Calendula at a glance
| Growing factor | What calendula need |
|---|---|
| Sun | full sun |
| Soil pH | 6.0–7.0 |
| Days to germination | 7–14 |
| Days to maturity | 45–60 |
| Spacing | 9–12 inches apart |
| Water needs | moderate |
| Cold tolerance | hardy |
| Family | Asteraceae |
Starting seeds
Calendula give you a choice: start seeds indoors for earlier flowers, or sow direct once the soil warms. For the earliest display, sow indoors a few weeks before your last frost — late winter in Zones 3–5, early spring in Zones 6–8, late winter in Zones 9–10 — and transplant out after the frosts end. For direct sowing, wait until the soil is workable and warming: late spring in Zones 3–5, mid-spring in Zones 6–8, early spring in Zones 9–10. Zones 11–13 are frost-free, so both methods work through much of the year; check your local extension service for the best local dates. Seeds germinate in 7–14 days. Keep seed mix or soil evenly moist until seedlings are up, and give indoor seedlings as much light as you can. Our seed starting calculator plans your indoor sowing date, and the germination time calculator estimates when to expect seedlings.
Transplanting and planting out
Transplant seedlings out after the last frost, on a cloudy day or in the evening so they do not wilt in the sun. Space plants 9–12 inches apart — that spacing is what keeps air moving and disease down — and water each plant in well. Our plant spacing calculator works out exactly how many plants fit your bed, and the square foot garden planner helps lay them out.
Soil and feeding
Calendula grow best in fertile, well-drained soil with a pH of 6.0–7.0. Dig in compost before planting — it feeds the soil and helps it hold moisture without getting soggy — and mulch after planting to keep the roots cool and the weeds down. Feed during the growing season with a balanced fertiliser at the label rate, roughly once a month while plants are actively growing, and stop feeding as the season ends. Our fertiliser calculator works out the right amount for your bed, and the compost ratio calculator helps you make good compost to dig in.
Watering
Calendula have moderate water needs: keep the soil evenly moist while plants are establishing and flowering, and water deeply rather than little and often so the roots grow down. Water at the base in the morning so the foliage dries during the day, mulch to hold moisture in, and watch for wilting in hot, dry spells. Our watering calculator gives a starting point for your bed size, and the watering schedule generator can build a routine around it.
Sunlight and temperature
Calendula need full sun — at least six hours of direct sun a day. Calendula are hardy and tolerate frost and cold weather well, so they can be planted out earlier and left in the ground over winter in most zones. In frost-free Zones 11–13, heat and a lack of winter chill can limit performance, so give them the coolest spot you have. Check your zone with the hardiness zone finder before choosing varieties. Our sunlight calculator can check whether your spot gets enough sun.
Pests and diseases
The pests and diseases to watch for on calendula are aphids, slugs, thrips. Calendula is rarely troubled by pests. Aphids can cluster on young growth, slugs may eat seedlings, and thrips can mark the petals in hot, dry weather, but the plants usually outgrow any damage. Check plants weekly, looking under leaves as well as on top, and act early. Hand-pick larger pests, knock aphids off with a strong spray of water, and remove badly affected leaves. Keep the area weed-free and avoid wetting the foliage when you water, since damp leaves invite fungal disease. Our pest identifier helper can help identify what you are seeing, and the plant disease checker helps narrow down leaf and stem problems.
Companion plants
Good companions for calendula are lavender, marigolds, garlic, chives. Lavender, marigolds, garlic and chives are good companions, and calendula itself is a valued companion for vegetables, where it attracts pollinators and hoverflies that eat aphids. Our companion planting finder can suggest more pairings for your bed plan.
Harvesting
Pick calendula flowers when they are fully open, in the morning after the dew has dried, for drying or for use in teas, creams and cooking. Dry the flower heads in a single layer in a warm, airy place out of direct sun, and store them in a jar once crisp. Deadhead regularly to keep the plants blooming — a calendula left to set seed slows down, while a deadheaded one flowers for months. Leave a few flowers to seed at the end of the season and they will self-sow. Our harvest date calculator can estimate your picking date from your sowing date, and the vegetable yield estimator helps you work out how much a bed will produce.
Common problems and fixes
| Problem | Likely cause | Fix |
|---|---|---|
| Plants go mouldy in wet weather | grey mould on spent flowers | Deadhead regularly and improve air flow. |
| Seedlings eaten | slugs | Protect seedlings and sow a few extra. |
| Flowers fade in summer heat | heat stress | Grow calendula as a cool-season flower and sow again in late summer. |
Plants go mouldy in wet weather
In wet summers, spent calendula flowers can go grey and mouldy, and the mould spreads to the leaves. Deadhead often so rotting flowers do not sit on the plant, keep to the spacing in the table, and water at the base rather than overhead.
Seedlings eaten
Slugs love young calendula seedlings, especially in damp spring weather. Sow a few more than you need, protect them until they are sturdy, and water in the morning so the soil surface dries by night.
Flowers fade in summer heat
Calendula flowers best in cool weather and sulks in summer heat. This is normal: enjoy the spring flush, then sow again in late summer for an autumn display, and in mild zones sow in autumn for winter and spring flowers.
Frequently asked questions
How long does it take to grow calendula?
From planting to maturity takes 45–60 days. Seed germination takes 7–14 days, and the total time depends on whether you start from seed, a nursery plant, or a bulb or cutting.
How far apart should I plant calendula?
Space calendula 9–12 inches apart. That spacing gives each plant room for air movement, which keeps disease down, and room to reach its full size without crowding its neighbours.
What soil pH do calendula need?
Calendula prefer a soil pH of 6.0–7.0. Test your soil before amending it — most garden soils are close enough, and guessing with lime or sulphur can do more harm than good.
Is calendula the same as marigold?
No, though they are related and look similar. Calendula (pot marigold) is a hardy annual in the daisy family with edible and medicinal uses, while true marigolds are a different genus. They grow in much the same way, though.
Can I eat calendula flowers?
Yes, calendula petals are edible and are used in salads, teas and rice dishes, where they add colour. Only eat flowers you have grown yourself without sprays, and use the petals rather than the whole flower head.