How to Grow Calendula
Add a sunny personality to the flower, herb or vegetable garden.
The name calendula means the first day of the month, presumably because this pot marigold blooms reliably at the start each day. It is easy to grow from seed, and quickly grows to maturity in 6-8 weeks after sowing.
Calendula or Calendula officinalis, is a hardy annual, and member of the Asteraceae or Compositae family, which share a central disc surrounded by spoon-shaped petals. Notable species include daisy, arnica, Artemisia, chamomile, chrysanthemum, dandelion and Echinacea.
Also known as Pot Marigold, English Marigold, Poet’s Marigold, or Summer’s bride, the original species were contained to yellow and orange single blossoms, yet many new hybrids have been bred to develop a range of differing shades of apricot, orange and yellow, with double ring of petals, as well as plants of shorter stature for borders, and longer stems for the cutting garden.
Often mistaken for the more familiar French and African pom-pom flowers known as marigolds, (Tagetes), it is not directly related, yet both produce bright yellow and orange blossoms that add a sunny personality to the flower, herb or vegetable garden.
When & Where to Plant Calendula
Your American Meadows order for Calendula will arrive as a packet of seeds, as plants are not available. Seeds can be sown directly in the garden, in the spring after danger of frost. Mark a row, and drop seeds every 6 inches, cover with ¼ - 1/2 “ soil, pat gently and water. Seeds should germinate within a week, and plants will blossom 6-8 weeks later.
Seeds can be started indoors in seed trays 3-4 weeks before frost-free date and transplanted into the garden. For a continuous display, sow several times throughout the spring either in the garden or in seeds trays for transplant. If you are not able to plant the seeds immediately, seeds can be kept in a dry location, away from sun and direct heat for up to a year.
Light: Full sun or part shade. Calendula will not do well in the hot summer heat and prefers the cooler temperatures of spring and early fall. Water regularly until well established, and when the soil is dry. Stress to the plants will cause the flower heads to droop and go to seed.
Soil: Calendula is tolerant of ordinary soil, yet prefers optimal conditions that offer rich, nutritious organic soil. Like most flowers and herbs, however, go easy on the fertilizer since too much nitrogen will create an abundance of foliage, and few flowers. Calendula does well naturalized in meadows and herb gardens, as well as in the flower border.
Spacing: Plant seeds in a row, allowing 5 inches between seeds, ideally along the edge of an herb, flower or vegetable garden. Mature seedlings can also be transplanted and grown in a window box and deck planter, with mixed flowers of deep blue and red to set off the brighter colors.
Planting: When direct sowing in the garden, or in a seed tray, press seed ½” below the surface of soft soil, cover with soil, press gently, and water. Keep in full sun, lightly watered until germination and plants appear.
How to Grow Calendula Throughout the Season
Growth Habit: Calendula is a medium sized plant, with a moderately sprawling, yet non-invasive growth habit. It thrives when planted in a clump with 6 or more plants. Under ideal conditions, Calendula can grow up to 15 inches tall, and a foot wide, depending on the variety. The foliage is minimal compared to the abundance of free flowering blossoms, which are short-lived and require, dedicated deadheading to keep a continuous succession of blooms. Colors range from orange, yellow, apricot to tawny red, bi-color and can be either single or double blossoms.
Staking: Not usually needed, yet may benefit from staking to keep plants contained and upright.
Watering: Regular watering is preferred, yet Calendula can flourish without supplemental water, and may add stress to the plant if especially dry conditions prevail.
Fertilizing: A layer of garden compost spread in the garden before sowing seeds will encourage healthy growth, yet over fertilizing will produce more leaves than flowers. Supplement mid-season with liquid seaweed or organic fertilizer spread at the base of the plant.
Mulching: Spring mulch with a layer of natural bark or hay around the base of the plants, may reduce weeds and keep soil moist.
Trimming & Pruning: Pinch off the spent blossoms behind the bud or at the base of the stem to encourage new growth. Pruning is not necessary, unless the plants become too vigorous. Sow several times during the season to extend the season and stagger bloom times.
Calendula: End of Season Care
Once a hard frost kills the plants naturally, remove the whole plant, pulling up the roots and bring to the compost pile. Save any seeds for the following year, or allow volunteer seedlings to sprout.
Dividing & Transplanting: Calendula will not easily divide. Best to sow the seeds in place and allow plants to flourish where planted. They will easily self-seed in place, to germinate the following season and create new plants.
Pests/Disease: Calendula blossoms are not susceptible to many pests, yet may develop powdery mildew if the weather is especially wet and conditions are crowded, Calendula blossoms attract a host of beneficial insects such as minute pirate bugs that control thrips, syrphidae that attack aphids, and micro-wasps that parasitize aphids.
Additional Concerns: Calendula is a short-lived annual, and thrives in cool weather. It may stop blooming in the heat of mid-summer, yet will likely start again in the cooler weather of fall if blossoms are kept deadheaded to encourage new growth and watered regularly.
To learn more about the plants we sell and how to grow them in your garden beds and patio containers, sign up for our inspiring emails.