Cauliflower

Growing Conditions

Cauliflower is the least forgiving brassica. It requires steady cool temperatures between 60°F and 70°F throughout its development. Temperatures below 50°F for extended periods cause buttoning in young plants. Temperatures above 75°F during heading cause loose, ricey, or discolored curds. The window of acceptable conditions is narrow.

Cold climates: For spring, transplant as early as possible — 4–6 weeks before last frost — to complete heading before summer heat. Fall plantings are more reliable: start indoors in midsummer, transplant 10–12 weeks before first frost.

Warm climates: Cauliflower is genuinely difficult in climates without a sustained cool fall. Focus on the most heat-tolerant varieties available.

Sowing & Planting

Start indoors 6–8 weeks before transplant date. Transplant at 4–6 weeks old, spacing 18–24 inches apart. Cauliflower does not recover well from transplant stress — handle roots carefully and water in well.

Care & Maintenance

Water consistently — 1–1.5 inches per week. Do not let plants dry out or sit in waterlogged soil. Side-dress with balanced fertilizer or compost at planting and when plants are 6 inches tall. Excess nitrogen promotes leafy growth over head development.

Blanching: For white varieties, tie outer leaves loosely over the developing head when it reaches 2–3 inches across. This prevents yellowing from sun exposure. Colored varieties (purple, orange, green) do not need blanching.

Common Problems

Buttoning — small, premature heads — results from cold stress on young transplants or planting out too early. Loose or ricey curds result from heat stress or inconsistent watering during heading. Browning of the curd can result from boron deficiency — apply a foliar boron spray if this is recurring. Cabbage worms and aphids affect cauliflower as they do all brassicas.

Harvest

Cut the head when it’s fully formed, compact, and white (or the intended color for colored varieties) before any separation or browning begins. Once the curd begins to open or separate, quality declines rapidly. Cut with a sharp knife leaving several outer leaves attached.

Varieties

White standard varieties (Snow Crown, Amazing) are the most common. Self-blanching varieties have leaves that naturally curl over the head, eliminating the need to tie leaves. Colored varieties — Cheddar (orange), Graffiti (purple), Romanesco (green, spiral) — are grown identically but don’t need blanching and are often more forgiving of temperature fluctuations.