When to Seed Kale
For a spring or early summer harvest, start your kale indoors four to six weeks before your last frost date, transplanting the seedlings about three weeks before your last frost date. For a fall harvest, sow your seeds in late July or early August. Kale can also be direct seeded into the garden. Certain frost protectant measures can be used to extend your growing season by several weeks for your fall harvest.
Where to Plant Kale
Kale will prefer a spot with full sun but can tolerate some shade - especially for spring crops. It will need well-draining, rich soil with a pH between five and seven. To increase the fertility of your soil ahead of planting, mix in two to four inches of compost and add additional high-nitrogen fertilizer if necessary.
Growing Kale
When transplanting, ideally your seedlings will be three inches in height. Plant your seedlings out 18 to 24 inches apart in rows 36 inches apart. You can also direct seed your kale. Plant seeds ½ inch deep and one inch apart, thinning to their mature planting distance. Applying mulch after transplanting (or germination if direct seeding) can help keep weeds in check and hold in moisture. The shallow roots of kale can be easily disturbed by weeding, so it’s best to avoid weeds in the first place! Ensure your seedlings get at least one inch of water per week.
Harvesting Kale
Kale can be harvested at any size, but established stalks will offer a continuous harvest through the cooler season. The plants should be at least eight inches tall before you start harvesting from them. Using sharp shears, clip off the lower leaves. Harvest no more than ⅓ of the plant at a time.