How to grow Collard Greens

Where to plant

Collards grow in a wide range of soils in full sun, ideally at a pH of 6 to 6.5. Mature plants withstand frosts and light to moderate freezes, and cold weather sweetens the leaves. A long cold spell after a good growing period makes them bolt, so choose a bolt resistant variety for spring.

In Florida, the Gulf South, Texas, the desert and Southern California, plant from fall through winter and harvest through the cool months. In South Carolina, Clemson gives spring transplanting from February or March into June and fall transplanting from August to October; the Mid-South and Mid-Atlantic are similar. Across the North, the Midwest, the Mountain West and Alaska, plant in spring and again in midsummer for a fall crop that carries on after frost.

Choosing a variety

Most collards are bred to be slow to bolt. Clemson recommends the hybrids Blue Max, Flash, Top Bunch 2.0, Tiger and Champion, a bolt resistant, productive and hardy variety, and the heirlooms Georgia Southern, introduced in the 1880s, Morris Heading and Vates.

How to plant

1. For spring, use transplants, as seed germinates slowly in cool spring soil. Start seed indoors six to eight weeks before your planting date.
2. For fall, sow directly in late summer, a quarter to half an inch (6 to 12 mm) deep in moist soil; seed sown deeper than half an inch often fails.
3. Keep the soil moist while seedlings establish, and thin at the three leaf stage.
4. Space plants 6 to 18 inches (15 to 45 cm) apart in rows 18 to 36 inches (45 to 90 cm) apart; wider spacing gives bigger plants for leaf by leaf picking.
5. Cover young plants with fabric row cover to keep out cabbage worms and harlequin bugs.

Watering and feeding

Water to keep moisture even, wetting the soil at least 6 inches (15 cm) deep, since light sprinklings give shallow roots. Water early in the day so leaves dry before night. Moisture matters most while seedlings establish and as plants mature. Mulch helps hold water and keep down weeds.

Collards need moderate fertilizer and plenty of nitrogen for good leaves. Work a fertilizer into the bed before planting according to a soil test, then side dress with nitrogen three to four weeks after planting and again three to four weeks later, keeping it 4 to 6 inches from the plants.

Pruning and care through the year

• Pick regularly from the bottom of the plant to keep new leaves coming from the top.
• Remove yellowing lower leaves and check under leaves for caterpillars and harlequin bugs.
• Rotate cabbage family crops to a new bed each year to reduce black rot and clubroot.

Harvesting

Collards are ready about 60 to 80 days after direct seeding. Either cut whole plants when half or fully grown, or, to extend the harvest, break off individual leaves from the bottom of the plant upward, taking only a few from each plant at a time. Plants can keep producing for months through the cool season.

Collards keep up to 2 weeks in a plastic bag in the fridge. Young seedlings can also be grown as microgreens, ready 10 to 15 days after sowing, using untreated seed.