Collards are a biennial in the mustard family (Brassicaceae) and are cool-weather edible garden plants. They have been cultivated for many centuries in Europe, Asia and Africa. Collards have large leathery leaves and can grow 2-6 feet tall depending on the variety with Portuguese cultivars being the tallest. They do best in full sun and in any amended garden soil. They can be directly sown in the garden or purchased as seedlings and planted in either spring or fall. In the south, they can be grown all winter long as they tolerate frost and light freezes. Provide adequate nitrogen for best results. Get a soil test before planting and fertilize according to the results. Depending on the variety, they can have a bitter to tangy flavor raw and mellow out with cooking. They tend to have the best flavor after a frost. Pick leaves before they have reached their full size for the best texture. Choose a variety that is slow to bolt to extend the harvesting season. Once flowers start to develop the flavor will diminish. Many cultivars have been developed to be slow-bolting. Plant collards in the edible garden or mix among the perennials to provide some green during winter. Click here to see a calendar of planting schedules, time-to-harvest, and recommended spacing. Insects, Diseases and Other Plant Problems: nematodes are a big problem in sandy soils. Diseases may include leaf spot and black rot and bacterial leaf blight. See pests of crucifers to the left. The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common Cole crop diseases and other plant problems. VIDEO Created by Elisabeth Meyer for "Edibles, Bulbs, and Houseplants," a plant identification course developed in partnership with Longwood Gardens. More information on Brassica oleracea .
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Aphids Found on Flowers and Foliage; Caterpillars Found on Flowers and Foliage; Slugs and Snails Found on Flowers and Foliage; Cabbage Looper on Ornamentals; Imported Cabbageworm on Ornamentals; Insect and Related Pests of Vegetables; Pests of Crucifers
Disease problems
Southern Bacterial Wilt on Herbaceous Ornamental Plants