When I talk about growing collards (Brassica oleracea) in Vermont, people think I’m a transplanted southerner. While collards are known as a southern green, there’s no reason you can’t grow them in the North, too. You might win over some southern friends if you invite them over for diner and serve collards greens and bacon.
Think of the collard as a headless cabbage. You grow them the same way, but instead of waiting for a head to form, you eat the large, flat, green leaves. Unlike other greens, though, this one needs to be cooked to taste its best. The leaves are tough and chewy raw. But like our more familiar, kale, collards are loaded with nutrition. Collard greens are high in vitamin A, C potassium and iron. And they’re easy to grow in our Northeast climate, mature quickly (60 to 70 days) and can take our erratic summer weather.
When to Plant
Collards grow equally well in cool and warm weather. As soon as the ground can be worked, sow seeds in April for an early summer crop. Sow every few weeks into summer to have a continuous supply of collard greens to eat. Greens grown in the heat of summer may be tougher than those grown in the cooler spring and fall.
Where to Plant
Collards don’t need full sun to produce. Locate the bed where it gets at least 2- to 3-hours of sun a day. the soil should be well drained and fertile.
How to Plant
Amend the soil with compost before planting. Sow seeds 1-inch apart in rows 2 feet apart. You can start seedlings indoors 4 weeks before planting or purchase transplants from the local garden center. Space transplants and thin the young seedlings to 6 inches apart and eat the in stir fries.
Care and Maintenance
Any green crop loves to have adequate nitrogen. Apply a high nitrogen fertilizer, such as fish emulsion and alfalfa meal, when the plants are 6 inches tall to stimulate more growth. Although collard greens are tough, they do appreciate and grow best when the soil is consistently moist. Mulching with an organic material such as untreated grass clippings or straw, allows the soil to stay weed free and moist throughout the growing season.
The same pests that attack cabbages, love collards as well. Watch for aphids on the leaves and spray insecticidal soap to control them. Although the thick, waxy leaves are less inviting for cabbageworms and loopers compared to broccoli and cabbage, they still may attack. Look for white butterflies in early summer. These lay eggs of cabbageworms and cabbage loopers on the collard leaves that turn into green caterpillars. Control this caterpillar with sprays of Bacillus thuriengensis (Bt).
Harvest collard greens by either hand picking selected outer leaves as needed or pulling the whole plant. By just picking the outer leaves, new leaves will form from the center and keep production going. You can start harvesting individual leaves when they are large enough to cook. You can also harvest the entire 2- to 3-foot tall plant when mature, about 60 days after seeding. Since the leaves are tough, chop them up well before sauteing and cooking.
‘Champion’ features blue-green leaves on a compact plant that’s slow to bolt. ‘Flash Hybrid’ has dark green leaves on a productive plant.
Excepted from the Northeast Vegetable and Fruit Gardening book.