Calendula will blossom all summer until the first heavy frost. Best sown directly outdoors after fear of frost (5/20-7/20), can be started indoors 4/21. Plant seeds ¼” deep, 2” apart in sun or part shade. 7-14 days until germination at 70°F. Plant 2-3 successions spaced 2-3 weeks apart for continuous blossoms. Cutting off dying flowers will encourage new buds to grow.
For cut flowers and medicinal use, harvest flowers when they are half open. For edible petals, harvest fully opened flowers. Do not eat the flower center or green parts.
Calendula flowers will produce seed if flowers are not harvested. Once seeds are dry on the plant, harvest by hand into a paper bag. Population size 20-50. Isolation ½ mile or caging.