A member of the Brassicaceae family, kale is related to broccoli, cabbage and cauliflower. It is a cool season biennial that is grown as an annual and is harvested for its tender foliage. Reliable and quick to harvest, growing kale is relatively easy because cold weather doesn’t bother it. In fact, cold weather makes it taste…well, a whole lot better!
Kale grows best in full sun and cool moist soil that is enriched with compost. Incorporate a legume cover crop, or work in 30 pounds of compost per 100 square feet before planting. Kale requires moderate amounts of fertilizer rich in nitrogen, phosphorus, and potassium.
Tip: Before you grow your organic garden, grow your soil. Consider adding soil amendments, like alfalfa meal (5-1-2), rock phosphate (0-3-0), greensand (0-0-3) and kelp meal, to your garden to improve the structure of the soil and provide a slow-release mix of nutrients to plant roots.
How to Plant:
Sow kale from seed or nursery stock in late summer for a fall harvest or early spring for summer harvest. Sow seeds 1/2 inch deep, allowing 1 foot between plants and 2 feet between rows. Fertilize with fish emulsion and kelp extract to encourage more growth.
Mulch around kale plants with a heavy layer of organic compost. This keeps the soil cool, prevents moisture loss, and provides readily available nutrients to the shallow feeder roots.
Like most winter vegetables, the taste improves after the first frost. In fact, we recommend that you do not harvest kale until after at least one or two hard frosts. Pick outer leaves as they develop or, harvest the entire plant. Kale matures 50-65 days after direct sowing or 30-40 days after transplanting.
Note: An extremely hardy plant, kale can be harvested as late as December in many areas and will over winter in warmer locations.
Insects and Diseases:
Relatively hardy, kale does not have many diseases or pest problems associated with it. Rotating crops helps to discourage many plant diseases, such as downy mildew and black rot. Watch for flea beetles and aphids and protect young plants from cutworms with a collar made from paper cups with the bottoms removed.
Seed Saving Instructions:
Biennial. Kale will cross-pollinate with all other Brassica oleracea, isolate by one mile the second year when going to seed. Before a hard frost, carefully dig the plants and pot them in sand. Store plants between 32-40 degrees F. Plant back out in early spring and allow to bolt. Harvest seed pods when dry and clean by hand.