When should I sow cauliflower in the UK?

Depends on type. Summer / autumn cauliflowers: March to May (modules); successional sowings every 3 weeks. Crops July–November. Winter cauliflowers (overwintering, also called heading broccoli): July to August. Crops the following March–May. Don't try to combine types in one sowing window — they're essentially different crops.

Why are my cauliflower heads so small?

Most likely: drought check during growth, poor soil, or a cultivar too vigorous for UK conditions. Cauliflowers need consistent moisture and fertile soil — any check to growth ruins the curd. Water deeply twice a week through summer; fork in well-rotted compost before planting. Mini cultivars (Igloo) are more forgiving than full-size standards if you can't guarantee consistent watering.

My cauliflower curd has turned yellow or grey — what happened?

Yellow: light exposure during development. Tie outer leaves over the curd from tennis-ball size onwards to shade it. Grey or brown patches: boron deficiency or fungal damage. Boron is added by a light dressing of borax (1 g per square metre) before planting. Fungal grey is usually from prolonged wet weather on a mature head; cut and use; doesn't affect the next crop.

What's the difference between standard, mini, and Romanesco cauliflower?

Standard heading cauliflower (Snowball, Walcheren): full-size white curds, 20+ weeks from sowing, the supermarket standard. Mini cauliflower (Igloo, Lateman): small heads, 14 weeks, suited to small gardens and successional sowing. Romanesco (Veronica): striking lime-green geometric curds, longer season, slightly more cold-tolerant; technically a different cultivar group but grown the same way.

Can I grow cauliflower in containers?

Mini cultivars (Igloo) in 30-litre containers work. Standard heading types don't have enough root space — they head poorly in containers. Use peat-free compost; water consistently; feed weekly. Net against cabbage white even in containers — they'll find them.

When and how do I harvest cauliflower?

Cut when the curd is full size, firm, and still tightly packed. Once buds start to separate (the curd looks rice-grained instead of smooth) it's going over and the texture coarsens. Cut early morning. Heads keep 7–10 days in the fridge; for longer storage, blanch and freeze florets.

Coliflor

Brassica oleracea var. botrytis

Sow cauliflower from March to May for summer–autumn cropping, or in July–August for autumn–winter heading types. Cauliflower is hardy (RHS H4–H5) — the least hardy of the common brassicas — and famously demanding: any check to growth (drought, transplant shock, nutrient gap) ruins the curd. Plant in firm fertile soil 60 cm apart; water deeply through summer; never let it dry out. Mini cultivars (Igloo, All The Year Round) crop in 14 weeks for small gardens; standard heading types take 20+ weeks. Tie outer leaves over the curd as it develops to shade and keep it white. Net against cabbage white and pigeons. Heads damaged by hard frost — winter cauliflowers crop only as far north as the Midlands reliably.

View full growing guide →