When to plant
Kale is a cool-season crop but far more cold-tolerant than most vegetables. Plant in early spring (6 weeks before last frost) for summer harvest, or plant in midsummer for fall and winter harvest. Kale survives frost down to -7°C and continues to grow in cool autumn weather when most other crops are finished.
Soil & site
Kale grows best in rich, well-drained soil high in nitrogen. pH 6.0–7.5. Work in compost before planting. Like all brassicas, kale benefits from soil with calcium and consistent moisture.
Feeding
Nitrogen is the key nutrient for kale's leafy growth. Feed with fish emulsion or a high-nitrogen fertilizer every 3–4 weeks. Side-dress with compost in midsummer. Stop heavy feeding 6 weeks before first frost to harden the plant.
Common problems
Cabbage worms (white butterfly caterpillars — check undersides of leaves weekly, hand-pick or use Bt spray). Aphids on new growth. Club root fungal disease in acidic soil — test and raise pH above 6.5 before planting. Flea beetles create tiny round holes — use row cover for young plants.
When to harvest
Harvest once leaves are 20–25 cm long. The lower, outer leaves are always harvested first. Darker green, deeply textured leaves have the most flavour. After a frost, kale becomes sweeter — cold converts starches to sugars.
How to harvest
Snap or cut off outer leaves one at a time, starting from the bottom of the plant and working inward. Leave the central growing tip and at least 4–5 inner leaves — the plant will keep producing from the centre for months. Avoid harvesting the topmost leaves which are the growing point. One plant can be harvested every 1–2 weeks indefinitely in good conditions.
Storage & use
Store unwashed kale in a bag in the refrigerator for up to a week. For longer storage, blanch leaves 2 minutes, shock in ice water, squeeze dry, and freeze. Frozen kale works in soups, smoothies, and stews. Kale chips (roasted at 150°C until crisp) keep in an airtight container for a week.
Companion planting
Kale thrives with aromatic herbs nearby that repel cabbage worms.
Useful for growing kale
A few things that make this one easier — chosen for this plant, not a generic list.
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