Calendula Seeds,
Yellow Porcupine

The ideal time to plant calendula depends on your climate. In colder regions, seeds should be started indoors in early spring, about 4-6 weeks before the last expected frost. In milder climates, it can also be sown in fall for winter blooming. The plant prefers cooler temperatures and may stop blooming during the peak summer heat, resuming again as temperatures cool​. If you’re not sure how to find your first and last frost dates, consult our blog post 'Our Experts Answer Questions, Share Resources.'

Calendula seeds can be sown directly outdoors or started indoors. For outdoor planting, sow seeds 1/4 inch deep after the last frost. Once seedlings are established, thin them to about 10 inches apart to allow room for growth. Keep the soil evenly moist during germination, which typically takes 7–14 days​. Calendula self-seeds readily, so allowing some flowers to go to seed can provide a natural source of new plants for the following year​.

This variety grows best in full sun but can tolerate partial shade, especially in hot climates. It prefers well-drained soil, rich in organic matter, but can tolerate poorer soils. Regular, moderate watering is recommended, avoiding overhead watering to prevent disease. Mulching can help retain moisture and suppress weeds. Deadheading spent blooms will encourage continuous flowering throughout the growing season.

Plants easily self-sow the following spring. If growing more than one variety of calendula, you will need to isolate by 1/4 mile from any other calendula varieties, or you can use caging techniques. Seeds are easy to save; the heads turn brown and seeds can easily be harvested in fall. Keep in a cool, dry, dark place until next spring.