Flash (F1) Collard Seed

Scientific name

Brassica oleracea

Culture

Collards like fertile, free-draining soil rich in organic matter, pH 6.0–7.5, with steady moisture for the best leaves. In the South they are grown mainly for fall, winter and early spring to avoid midsummer extremes, though they take some heat. They are very cold hardy, and frost and cold improve their flavor in the North.

Days to maturity

Counted from direct sowing; transplants are ready about 2 weeks sooner.

Direct sowing

Sow from early spring until about 3 months before fall frost. For bunching, drop 3–4 seeds every 12–18", 1/2" deep, in rows 18–36" apart, and thin to one plant per spot. For baby leaf, sow about 60 seeds per foot, 1/4–1/2" deep, in a 2–4" band.

Spring transplants

Sow 2 seeds per cell in 50- to 72-cell trays, or 3–4 seeds per inch in open flats, 1/4" deep; plants are ready in 4–6 weeks. Keep the soil above 24°C (75°F) until germination if you can, then grow on near 16°C (60°F). Plant out 12–18" apart in rows 18–36" apart. Collards grow best at 13–24°C (55–75°F), ideally 16–21°C (60–70°F), but still produce well in summer.

Fall and winter crops

For fall, start seedlings in May and plant out in June or July; sow early where hard freezes come early. Where winters rarely drop below 32°F (0°C), set out transplants from September to February.

Insect pests

Row cover laid at planting is the most effective way to keep insects off.

Disease

Prevention is key: long rotations away from cabbage-family crops, clean seed-starting mix and seedbeds, and strict sanitation.

Harvest

Start picking individual leaves about 2 months after planting. Leaves keep improving with light frosts into late fall. Late-summer plantings can be overwintered in cold frames or hoop houses, or in the open where winters are mild; row cover extends the season.

Packet

100 seeds.

Seeds per lb.

About 85,200 on average.