Grow Calendula From Seed: Sowing, Harvesting & Saving Seeds

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Growing calendula from seed is easy and will reward you with cheerful golden flowers that you can use in herbalism, food recipes, skin care, and natural dyeing. Use this expert guide to ensure growing success and get the scoop on interesting varieties to grow for skin care and medicinal properties.

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Calendula officinalis, known by many as the “pot marigold”, is a pretty and easy-to-grow plant that you’ll find in many herb gardens. Though it’s different from the Tagetes species marigolds that most people are familiar with, it too has pretty yellow to orange flowers. It’s these flowers that people grow calendula for since they have many therapeutic and creative uses in cooking, herbalism, skincare, and artisan crafts.

Calendula has colonized the temperate world thanks to its useful and hardy nature and will grow in most soil types. It will even tolerate partial shade. The plants do best in full sun, though, especially on well-drained soil. Plant them there, and they’ll reward you with countless flowers throughout the growing year.

I’ve grown calendula for well over fifteen years (and counting!), and though it’s an easy, beginner-friendly plant, I have some valuable advice to share. Let’s get started.

Calendula Growing Basics

Botanical name	Calendula officinalis
Common name	Pot marigold
Plant type	Hardy annual/may overwinter in mild climates
Sun	Full sun, light shade tolerated
Soil	Well-drained, ordinary garden soil
Sow	Spring or autumn
Sowing depth	About 0.5 cm / ¼ inch
Spacing	About 23–37 cm / 9–15 inches
Germination	Usually 1–2 weeks
Flowering	Summer into autumn
Harvest	Pick flowers regularly

Choosing Calendula Varieties

The first step in growing calendula flowers is choosing a variety. There are many to choose from, and if you’re growing them for cooking, any one you like the look of will do. Yellow-petalled varieties are very pretty as cake decorations or sprinkled on salads. Orange varieties have the most color and create stunning calendula-infused oil.

You can also get pale yellow, bronze, and pink varieties. Besides colors, calendula can have different petal shapes and single and double varieties. Some of the most beloved general-purpose calendula varieties are:

Indian Prince — Deep orange blooms with dark centers.
Orange King — Bright orange, large double flowers.
Fiesta Gitana — Vibrant, compact, mixed-color blooms.
Pacific Beauty — Reliable, colorful, long-flowering garden favorite.
Pink Surprise — Soft pink, unusual calendula flowers.

High-Resin Calendula

Calendula is popular in herbal medicine and botanical skincare. However, the usual way that they’re sourced is by purchasing them dried. If you’ve purchased them before, you might notice how pale and straw-like the flowers can be. If you then grow and start drying your own, you’ll see that the highest-quality flowers you can source will come from your own garden. You’ll also know exactly what you put on the plants and in the soil, and you can ensure they’re organic and safe to eat and for skin.

Close-up of a bright yellow calendula flower. — Calendula ‘Resina’ is marketed for high resin amounts.

If you want to grow calendula specifically for herbalism and botanical skincare, choose one or a mixture that is higher in oil-soluble active constituents. One way that herbalists gauge this is to look for varieties high in “resins.” This is a term for the sticky substance you can feel on the flowers, and it can contain various natural plant chemicals used in herbal medicine.

A wooden trug is filled with large orange calendula flowers. — I currently only grow Erfurter Orangefarbige for its size, color, and potential skin benefits.

When you pluck calendula flowers to harvest, you will feel stickiness on the back and on the upper part of the stem. The stickiness can indicate that the flower contains more resinous material, which is associated with oil-soluble compounds such as triterpenoid esters. That’s why Resina (modest yellow flowers) and Erfurter Orangefarbige (huge orange flowers) are popular in the herbalism world.

Calendula Varieties for Herbalism

However, resins aren’t always an indication of the highest quality of active constituents—compounds such as triterpenoids, carotenoids, flavonoids, and faradoil esters. Fortunately, there have been a few studies looking at the levels of these constituents in various cultivars.

A large glass jar filled with golden oil and dried calendula flowers. — You can use dried calendula flowers to make calendula-infused oil

Based on published phytochemical studies, these are some interesting cultivars to consider if you’re growing calendula specifically for herbalism or skincare. Most are difficult to find and source, though, and the levels of beneficial compounds in your homegrown flowers will vary based on growing conditions, harvest timing, plant quality, and extraction method:

Calypso Orange Florensis¹ → strongest documented triterpenoid-ester profile
Erfurter Orangefarbige² → particularly interesting faradiol + flavonoid profile
Radio³ → excellent flavonoid + carotenoid combination
Dracon⁴ → highest documented carotenoid concentration
Double Ball⁵ → highest documented essential-oil yield (aka Ball’s Double, Ball’s Improved Orange, or Ball’s Orange)

Starting Calendula from Seed

Calendula seeds remind me of tiny brown seahorses, and they reliably germinate at mild temperatures between 59-77 °F (15-25 °C). They can take 1-2 weeks to emerge, and it takes a further 6-8 weeks for the tiny seedlings to grow to full size and start producing flowers.

Complete Guide on how to grow Calendula Flowers including tips on sowing, growing, saving seed, ways to use it as a companion plant, and the best cultivars for medicinal use #lovelygreens #herbalism #marigold #calendulaofficinalis — Sowing calendula seeds in a row.

Though I successfully start calendula seeds in modules, small pots, and trays, calendula seeds grow best if sown about 1/4″ (0.5 cm) directly in the soil. That could be in an in-ground garden bed, raised bed, or even the surface of a large pot. In early spring, sprinkle them lightly in a row or broadcast-sow them across an area and rake the seeds in. Keep the soil or potting mix moist, and you can expect to see seedlings emerge after a week or two.

If you have mild winters such as in the British Isles or zones 8-10 in North America, you can sow them in early autumn. Starting them then and overwintering the young seedlings with protection can give them a head-start on spring. If all goes well over winter, the small plants will start growing quickly once it warms up. They can produce flowers several weeks earlier than spring-sown seeds.

Succession Sowing Calendula Seeds

Calendula is a seed that I sow only once a year in spring. The flowers start blooming a couple of months later, when I start harvesting. I’ll carry on picking and drying flowers until the end of August, then stop. As long as I keep picking, more flowers will bloom, though they do seem smaller by the end of summer. The leaves and stems start getting a bit battered by powdery mildew at this time, too.

A herb spiral made of red bricks. Growing at the top are calendula, sage, and thyme. There are other herbs growing below, including Korean mint, summer savory, and chives. — Calendula flowers growing in my diy herb spiral

If you would like a fresher crop of flowers to start blooming after your first sowing, you could succession sow. This means sowing more seeds every two to three weeks throughout spring. One wave of calendula flowers could follow the next, and you could remove any that showed signs of disease or smaller flowers.

Calendula Growing Tips

Calendula does incredibly well in most open situations and is an easy-to-grow plant. It can even thrive on neglect and, in the right conditions, will grow better for being left alone. That said, the calendula that I grow does so much better in its preferred kind of soil and situation, and given enough space.

When siting your plants, keep in mind that calendula is truly sun-loving and does best if it has 6+ hours of direct sunlight. In shady places, they won’t grow well or produce many flowers and may disappoint you. Sow calendula seeds in the right situation, with the best soil type and spacing, and you’ll be on your way to healthy plants and flowers!

Best Soil Type & Mulch

Calendula prefers moderately fertile, well-drained soil that’s about pH 6-7. It’s not particularly fussy, though, and will grow, if not thrive, in most soil types. In dry or nutrient-deficient soils, calendula plants can look a little scrappy and produce fewer and smaller flowers. In overly fertile soils, such as those that have had compost or manure dug in, it can produce many more leaves than flowers.

A large bed of dozens of calendula plants. They are blooming with orange flowers and grow in between two long lavender hedges. — I grow calendula flowers in my fertile no-dig garden beds.

Contrary to what other growing guides may say, in my garden they produce far more flowers if the soil around them is mulched. I use garden compost around mine, and not only does it help reduce weeds, but it also creates a moisture-retentive crust above the soil level that will leach nutrients down when it rains. I get spectacular harvests by growing calendula this way.

Looking slightly up at a 2.5 wide calendula flower bed leading up to a polytunnel. There are dozens of plants flowering with orange flowers. The ground the plants are growing in is covered with a chunky dark brown compost. — Though the topsoil is only an inch deep here, compost as a mulch keeps the calendula plants healthy and flowering.

If you already have compost mulch on your soil, you can sow calendula seeds directly into it. Otherwise, apply mulch after the plants are about 2″ (5 cm) tall. Don’t cover the base of the plant, but bring the mulch close to it.

Calendula Plant Spacing

When growing calendula from seed, you’ll get a lot of seedlings coming up at a time. That means you will either need to thin them out and send the unneeded ones to the compost heap or transplant them elsewhere. When 1-2″ (2.5-5 cm) tall, they are a dream to transplant and will take to their new bed quickly if you keep them well watered. This year I even transplanted bigger seedlings and they, too, grew, but I did worry that they were looking a little sorry for themselves at first.

Looking down at the end of a wood-edged in-ground garden bed that's about four and a half feet wide. There are three rows of young calendula plants growing, each about a foot apart. — Plenty of space around each plant can mean healthier calendula and more flowers.

Calendula plants can grow up to two feet (60 cm) tall and fill out an area 18-24″ (45-60 cm) in diameter. So, once the seedlings are up, you should weed (or transplant) them to the best spacing. Each plant should ideally be spaced about 9-15″ (23-37 cm) apart in all directions. They’ll jostle right up against one another at this spacing but have enough space to grow and support their neighbors. Also, though the seedlings look small, they will completely fill that space over a matter of weeks.

Looking down at a densely planted bed of calendula flowers. — When planted 12″ apart, calendula plants support one another but aren’t overcrowded.

Though the plants can grow fairly close together, overcrowding can cause issues. It creates a higher chance of them succumbing to powdery mildew earlier (especially in hot summers) or not producing as many flowers. The density also creates habitat for slugs. So, once your seedlings come up, thin them out so that they have room to grow to their potential.

Growing Calendula in Containers

Calendula is adaptable, and though it prefers growing in the ground, it will also grow in outdoor pots, containers, and window boxes. Aside from the harvest of flowers, they’ll also add a splash of color throughout most of the year. When growing in containers, make sure that the compost is moist but has good drainage.

You can use any multipurpose potting mix to grow them in, but keep in mind that spacing rules still apply. That means that you might choose to grow only one plant in a single pot.

Powdery Mildew

If calendula is too crowded or water-stressed, then it can suffer from a fungal disease called powdery mildew. You’ll notice it as a light covering or speckles of light gray over the leaves. It starts on one leaf, then spreads from there to the rest of the plant and neighboring plants. It’s a common problem if the soil is dry, the sun is hot, and especially if nights are humid.

Calendula plants growing in a raised bed. Some of the leaves have a silvery coating on them. — The silvery coating on the leaves is powdery mildew.

Though it won’t kill your plants right away, powdery mildew weakens the plant, slows flower production, and readily spreads. If it’s a really bad case, you may decide to take the plants out earlier than you would need to.

Close-up of a calendula plant that's leaves are covered with a powdery substance. The lower leaves are yellowing, too, and it does not have flower buds. — Powdery mildew has weakened and sickened this plant.

To prevent powdery mildew, keep lots of airflow around each plant, and make sure the plant is growing in moist but free-draining soil. If you’re watering calendula, do so early in the morning so that excess evaporates off during the day and doesn’t contribute to increased humidity at night.

In my garden, powdery mildew happens almost inevitably, but I want it to happen in late summer or autumn rather than in the middle of the growing season. When affected, the flowers are still perfectly fine to harvest and use, and I keep harvesting them until I pull the plant up to compost.

Pests and Disease

Besides powdery mildew, calendula can also suffer from diseases and conditions such as aster yellows, smut, root rot, rust, and leaf spot. I’ve had aster yellows on mine before, and the flowers grow in bizarre ways, such as lots of tiny green stems growing out of a flower head, each with a mini flower at the top. It causes other deformities, too, such as strange green flower growth.

Looking at the side of a metal raised bed overflowing with calendula leaves and orange flowers. — Densely planted calendula growing in a ‘Mist Green’ metal raised bed.

To prevent disease, practice good garden hygiene by removing dead and affected foliage, increasing airflow, and watering at the base of the plant, not the leaves. Watering leaves can increase humidity, which in turn encourages fungal growth.

Standing back and looking out over a large bed filled with hundreds of calendula flowers. You can also see marshmallow plants growing behind, lavender growing at the sides, and yarrow, comfrey, and other flowers growing around. — Calendula is an important crop in my skincare garden.

Calendula can also suffer from aphid attacks. If you notice them on your flowers, you can try to knock them off by gently spraying the flowers with water. Calendula naturally attracts aphid predators like hoverflies and ladybirds, so with patience you can also just wait for them to take care of the problem for you.

Harvesting Calendula Flowers

Calendula flowers are daisy-like and usually a buttery yellow to bright orange. They’re also fairly hardy and tend to produce flowers from spring right through to the first frost. It’s not uncommon to see your plants optimistically opening up new flowers in the middle of winter, though. When you spot one holding out against the cold and rain, it can’t help but make you smile.

A woman wearing an apron is on her knees beside a raised bed. She's reaching inside to pick yellow calendula flowers. — Harvesting Calendula ‘Resina’

Once calendula is in bloom, start picking. The more you pick, the more flowers the plant will produce, so don’t be afraid to pick every fully blooming flower. There will be more within a few days! When you harvest calendula flowers, do it on a dry day once the flowers are fully open. Then, dry them thoroughly before storing them in sealed containers kept in a dark cupboard.

Looking at a raised bed filled with huge orange calendula flowers. You are at eye level. — Pick calendula flowers when they are dry and fully open.

If you are picking flowers for therapeutic purposes, be aware that their levels of active constituents may begin dropping when it starts getting hot. A study⁶ has shown that once temperatures increase beyond 89°F (32°C), the active constituents in calendula flowers decrease.

Looking down at a hand holding a wooden trug filled with yellow calendula flowers near a healthy calendula plant covered in orange flowers. — Pick each flower by hand, snapping the stem a little under the base.

As the summer progresses, you might find that calendula plants become tall and spindly. If so, you can trim them back to encourage new growth and flowers. Use pruners/secateurs or your fingers to pinch back to a leaf node. In warm climates or during a hot summer, you may also find that your plants stop blooming. They’re bearing through the heat and, if you keep them watered, they can start flowering again when temperatures cool down.

Calendula Hardiness

Although it’s pretty hardy, calendula is usually grown as an annual in regions with winter temperatures that dip below freezing. Few, if any, plants can survive prolonged cold, so you would grow calendula from seed again in spring. Fortunately, they are prolific seed producers and will self-seed, whether you want them to or not.

Calendula flowers blooming in between rows of elephant garlic. — I let these self-seeded calendula plants grow between my elephant garlic.

These seeds fall from the plant to the ground and quite contentedly overwinter in the soil. Then, when it warms up in spring, you will have masses of new calendula seedlings germinating in the same place. Sowing calendula seeds once can mean an almost permanent calendula flower bed, provided that you care for the volunteers.

In mild places, and if the plants are protected against frost, calendula plants can survive for at least a couple of years. A few of my plants survive each winter, though their lower stems sometimes darken and become leggy. In spring they grow again, producing new leaves and flowers!

Saving Calendula Seeds

Leaving self-sown seeds to grow volunteer plants is the easy way to grow calendula from year to year. However, if you’d like to grow them in a different location, or share seeds with a friend or at a seed swap, saving calendula seeds from your plants is easy.

Close-up of a dried, brown, calendula seed head still attached to the plant. — There are about 18 seeds ready to harvest on this calendula seedhead.

Each calendula flower can produce at least a dozen seeds, and each plant can produce many flowers. That means that a single plant can provide you with more than enough seeds! In fact, all of the dozens of Erfurter Orangefarbige calendula flowers in my garden currently are from a handful of seeds I saved from one surviving plant. If I hadn’t saved those few seeds, I wouldn’t have had any to grow when we moved house.

Close-up of an open hand holding the many seeds just pulled from a dried calendula seedhead. — Dried calendula seeds are easy to harvest by just pulling them from the seed head.

As they mature, calendula flowers lose their bright petals and start swelling as they transform into seedheads. They start off green but eventually mature and dry to brown—it’s then that you can collect them from the plant. You can either cut them whole from the plant before the seeds are released or pull the seeds from the seedheads using your fingers.

A tall glass jar filled with hundreds of brown calendula seeds. Maybe thousands. — Store calendula seeds in brown paper bags or in jars if they are completely dried out.

Alternatively, you can cut the seed heads with six inches or more of the stem. Tie the cut long stems with a string and then place the flower heads in a brown paper bag. Tie it on so that it won’t fall off, then hang the stems upside down in a warm and airy place until they are dry. Give the bag a good shake after this, and most of the seeds will fall off. Calendula seeds should be sown within 3-5 years for the best viability.

Calendula Flower Uses

Though you might be like me and grow calendula as a herb or a pretty flower, they have so many uses. In the garden, you can grow them as companion plants—their flowers attract pollinators and hoverflies (good guys) to your patch and can lure aphids away from prized vegetables. You can even sometimes see aphids get stuck in the sticky resins under the flower heads.

A tabletop display of various calendula skincare products. A stack of soap with tiny flecks of calendula petals in them. Bath salt with flower petals, brown jars of skin cream, a tin of golden salve, and bath fizzies decorated with dried flowers. — The recipes for these calendula products are in this ebook.

In traditional herbal medicine ⁷, calendula flowers are used in preparations for minor skin inflammation and wounds, as well as minor mouth and throat inflammation. These benefits also make calendula extract valuable in herbal skincare, such as in calendula skin cream and as a natural soap colorant. I have a lot of ideas for using calendula on Lovely Greens, especially in botanical skincare. Here are some ideas that will get you started:

Sources

Calypso Orange Florensis → strongest documented triterpenoid-ester profile. Neukirch et al. (2004), Phytochemical Analysis — directly compared 10 Calendula officinalis varieties using HPLC and found Calypso Orange Florensis produced the highest amounts of the measured bioactive triterpenoid monoesters. ↩︎
Erfurter Orangefarbige → particularly interesting faradiol + flavonoid profile. For faradiol, Della Loggia et al. (1997) screened 1,200 individual plants from 20 commercial origins and selected Erfurter orangefarbige, gefüllt blühende because its TLC fingerprint showed a high amount of the faradiol esters. ↩︎
Radio → excellent flavonoid + carotenoid combination. Raal et al. (2016), Natural Product Communications, measured 24 commercial cultivars. Radio reached 1.7% total flavonoids and 2.5% total carotenoids, making it particularly notable for the combination. ↩︎
Dracon → highest documented carotenoid concentration. Raal et al. (2016), Natural Product Communications, found total carotenoids across the tested cultivars ranged up to 2.7%, with Dracon being the highest cultivar. ↩︎
Double Ball → highest documented essential-oil yield. Again, Raal et al. (2016), Natural Product Communications, found that among the eight cultivars for which essential-oil yield was measured, Double Ball produced the highest yield at 0.43%. ↩︎
Barut and Tansi (2024) found that increasing temperatures and delayed harvesting were associated with reductions in flower size and yield, while flower essential-oil composition also changed, with several major constituents decreasing as temperatures increased. ↩︎
In traditional herbal medicine, calendula flower is used for minor skin inflammation and wounds, and for minor inflammation of the mouth and throat. These uses are recognized by the European Medicines Agency as traditional uses, although clinical evidence is not sufficient to draw firm conclusions about effectiveness. European Medicines Agency — Calendula flower ↩︎

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