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Vegetables · Cool-season biennial grown as annual

Kale

Brassica oleracea var. sabellica

Frost only makes it sweeter — kale is the cold-hardy leafy green that earns its keep from first planting through winter's worst.

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Sunlight
Full sun to part shade
Water
1-1.5 in per week
Harvest
50-65 days from transplant; harvest outer leaves any time after 8-10 in tall
Hardiness
Zones 7-10 as overwintering crop; tolerates frost to 10°F (-12°C)
About

The Green That Thrives on Cold

Kale has been feeding people for over 2,000 years, long before it became a farmers-market darling. A non-heading member of the cabbage family, it comes in a range of forms — the crinkled Scots curly types, the dark and blistered Lacinato (Tuscan or dinosaur kale), and the broad-leafed Red Russian — each with its own texture and mild-to-earthy flavor profile.

What sets kale apart from most vegetables is its cold-hardiness. A hard frost converts leaf starches to sugars, genuinely improving flavor. Plants that survive a freeze often taste better than anything grown in warm conditions, making fall and winter the true kale season for gardeners willing to wait.

How to grow

Planting & care

Direct-sow seeds 1/4-1/2 in deep, 6 weeks before last frost in spring, or 6-8 weeks before first frost for a fall crop. Thin or transplant to 12-18 in apart. Kale prefers rich, well-drained soil with a pH of 6.0-7.0 and benefits from a balanced fertilizer or compost worked in at planting. Keep soil consistently moist, especially during establishment.

Side-dress with a nitrogen-rich fertilizer 4-5 weeks after transplanting to push leafy growth. Mulch around plants to retain moisture and regulate soil temperature. Harvest outer leaves first, leaving the central growing tip intact to keep plants productive for months. Watch for cabbage loopers, aphids, and imported cabbageworms — row covers early in the season prevent most pest pressure.

Good to know

Cut-and-Come-Again Harvesting

Kale rewards a restrained hand. Never strip a plant bare — remove no more than one-third of the leaves at a time, always working from the outside in. Treated this way, a single plant can produce continuously for 6-8 months, from spring through hard winter freezes in most climates.

Common questions

How much sun does Kale need?

Kale grows best in full sun to part shade.

How often should you water Kale?

Give it about 1-1.5 in per week.

When is Kale ready to harvest?

Kale is usually ready in 50-65 days from transplant; harvest outer leaves any time after 8-10 in tall.

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