How to Grow and Use Calendula

By: Angela Judd | November 16, 2024

Calendula flowers greet the morning by blooming and then close again each night. This easy-to-grow flowering herb is a favorite companion plant that adds a beautiful pop of color to my cool-season garden. Learn how to grow calendula with these five tips.

Article Index

Plant Calendula Throughout Your Garden as a Companion Plant
Plant at the Right Time for Your Climate
Keep Calendula Looking Good
Don’t Forget to Harvest
Use It! You’ve Grown It Organically and Know Exactly Where It Came From

1. Plant Calendula Throughout Your Garden as a Companion Plant

Calendula is one of the most popular companion plants for nearly every crop in the garden. I plant one in just about every garden bed. Calendula prefers full sun but can grow well in partial shade so that you can plant one anywhere. I try to add a flower and herb to each garden bed, and calendula is easy to add. It’s one of my favorite cool-season companion plants.

It attracts beneficial insects that help keep pest populations in check and aid in pollination, including bees, hoverflies (Syrphid flies), ladybugs, lacewings, butterflies, and other pollinators. This guide explains how to attract beneficial insects. In this guide, discover the benefits of insect hotels and learn how to effectively use them in your garden to attract beneficial bees and lacewings.

2. Plant at the Right Time for Your Climate

Calendula (also called pot marigold) prefers cool weather. Plant calendula just before the last spring frost in cold-weather climates. It tolerates temperatures down to 25°F (−4°C).

In hot summer/mild winter areas like Arizona, calendula grows best throughout the cooler months of late fall and spring. The ideal temperature range for flowering is between 60–80°F (16–27°C).

In the low desert of Arizona:

Plant seeds or transplants outside: September 15 – November.
Calendula blooms in Arizona from December through May.

Get calendula seeds here.

Plant calendula seeds ¼ inches deep (6 mm) in fertile, well-draining soil. Thin seedlings to 6 to 12 inches apart (15 to 30 cm). Keep soil moist until the seeds sprout. When choosing transplants, smaller is usually better, as smaller plants adapt more easily to planting. In square-foot gardening, plant 1–4 calendula per square foot (10–40 per square meter).

3. Keep Calendula Looking Good

Calendula needs regular water; do not let the plant dry out. Keep flowers deadheaded to encourage more blooms. Calendula does not require supplemental feeding.

If it looks a bit haggard, cut plants back to about 3 inches (7.5 cm) to promote new growth. It is susceptible to powdery mildew. Learn effective powdery mildew treatments here. If a plant becomes severely infected, remove the plant and throw it in the trash (not compost).

4. Don’t Forget to Harvest

The more you harvest, the more calendula will grow. Harvest calendula blooms when the petals begin to open—fresh, young, and just fully opened. Avoid collecting heads that are already starting to dry and form seeds. You can leave those on the plant to fully dry and mature for seed-saving instead.

Calendula reseeds easily due to the many seeds produced on each bloom. Blooms left on the plant quickly develop into seeds. Calendula seeds are ready to harvest when they turn brown. Save seeds to share and plant next season. Learn more in this seed-saving guide.

5. Use It! You’ve Grown It Organically and Know Exactly Where It Came From

Calendula petals are edible. The entire calendula flower is used in salves, oils, and teas. Learn more about edible flowers.

Dry the flowers completely by dehydrating for at least 72 hours at 100°F (38°C). Store dried calendula blooms in an airtight container out of direct sunlight, and use within one year.

Here’s how I use it:

Tea: Steep 1–2 tablespoons (15–30 ml) in 8 ounces (240 ml) of water.
I add it to my chicken nesting boxes as a natural insect repellent and feed my chickens fresh petals. They love them, and it makes their yolks even more vibrant!