Sowing and Transplanting Cauliflower: Cauliflower requires slow, steady growth in cool weather. Hot weather will cause cauliflower to bolt or button up (cold weather will also cause cauliflower to button—not form full-sized heads). Start cauliflower in early spring 4-6 weeks before the last frost then transplant seedlings after the last frost. In mild-winter regions start cauliflower in autumn to mature in the mild winter. Sow seeds ¼-½” (6-13 mm) deep. Seed will germinate in 4-10 days at 65°F (18°C). If you sow seed indoors to start, choose a warm, well-lighted location—in a bright window or under grow lights.
Growing Cauliflower: Seedlings can be transplanted into the garden when they are 4-5” (10-13 cm) tall after the last frost. Move seedlings to a sheltered place outdoors to “harden off” 1 week before transplanting. Thin plants to 15” (37.5 cm) apart in a staggered pattern. Grow cauliflower in rich, well-drained soil, in full sun. Give cauliflower regular water keeping the soil evenly moist. Feed cauliflower every 3-4 weeks with fish emulsion or compost tea. Blanch curds to improve flavor; fold the outer leaves over the head and tie or pin them at the top with a rubber band
Harvesting Caulifower: Cauliflower matures 70-120 days after sowing; 55-80 days after transplanting. Cut when the heads are firm and tight and reach 4-8” (10-20 cm) in diameter and curds are still tight. Cut the stalk just below the head. In warm weather, harvest about 4 days after tying the leaves for blanching. Store head unwashed and wrapped in plastic in the refrigerator.
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