Collards are a cool-weather crop. Start seed indoors 4 to 6 weeks before the last frost in spring. Sow seed outdoors when the soil can be worked in spring. Place transplants in the garden when they are 3 to 4 inches tall (7-10cm) as early as 3 to 4 weeks before the last frost in spring. In mild-winter regions, start seed in late summer for a winter or spring harvest.
Description. Collards are a hardy biennial grown as an annual. Collards grow 2 to 3 feet tall (.6-.9m) with rosettes of large, non-heading, waxy leaves growing on sturdy stems. Collard is a kind of kale and a primitive member of the cabbage family.
Yield. Plant 2 to 3 collard plants per household member.
Site. Grow collards in full sun. Collards prefer organically rich well-drained soil with a pH of 6.5 to 7.5. Add aged compost to planting beds in advance of planting especially where the soil is sandy.
Planting time. Collards are a cool-weather crop and can tolerate temperatures as low as 20°F (-6.7°C). Collards are more tolerant of heat than cabbage. Collards are usually grown from transplants. Start seed indoors 4 to 6 weeks before the last frost in spring. Sow seed outdoors when the soil can be worked in spring. Place transplants in the garden when they are 3 to 4 inches (7-10cm) tall as early as 3 to 4 weeks before the last frost in spring. In most regions, collards can be planted in early spring and again in late summer for fall or winter harvest. In late summer, directly sow seed in the garden. In mild-winter regions, start seed in late summer for a winter or spring harvest.
Planting and spacing. Sow seed 1 inch (2.5cm) deep and 3 inches (7.6cm) apart. Thin collards to 12 inches (30cm) apart when seedlings are big enough to lift by their true leaves. Space rows 24 inches (61cm) apart. Transplant thinned seedlings to another part of the garden when plants have 4 or 5 true leaves. Transplants that are leggy or have crooked stems should be set deeply up to their first leaves so that they won’t grow to be top-heavy.
More tips at: Collard Seed Starting Tips.
Companion plants. Tomatoes, southern peas, peppers. Do not plant with celery, potatoes, yams.
Container growing. Collards can be grown in containers. A single plant can be grown in a 10-inch (25cm) pot. In larger containers set collards on 18 to 24 inches (45-61cm) centers.
Caring for Collards
Water and feeding. Water collards regularly so that leaves do not grow tough. Under-watering may cause collards to become stringy. Add aged compost to the planting bed before planting and side-dress plants with compost at midseason. Aged manure can be added to planting beds in the autumn before planting.
Care. Mulch around collards to keep the soil moist. Plants that grow top-heavy may need staking.
Pests. Collards may be attacked by cabbage family pests: cutworms, cabbage loopers (preceded by small yellow and white moths), and imported cabbage worms. Handpick these pests or spray plants with Bacillus thuringiensis.
Diseases. Collards have no serious disease problems.
Harvesting and Storing Collards
Harvest. Collards are ready for harvest 85 to 95 days from seeding and 75 to 85 days from transplanting. Pick or cut leaves on a cut-and-come-again schedule as soon as plants reach12 inches tall. Harvest young, tender leaves from the bottom up; cut leaves before they get old and tough. Frost will cause some of the carbohydrates in the plants to turn to sugar and can make leaves sweeter tasting. Complete the harvest before the first hard freeze.
Also see: How to Harvest and Store Collards.
Storing and preserving. Collards can be stored in the refrigerator for up to one week or in a cold moist place for 2 to 3 weeks. Collards can be frozen, canned, or dried.
Collard Varieties to Grow
Varieties. ‘Blue Max’ (68 days); ‘Champion’ (60-80 days); ‘Georgia’ (70-80 days); ‘Top Bunch’ (67 days); ‘Vates’ (55-80 days).
Common name. Collards
Botanical name. Brassica oleracea acephala