Cauliflower

Sun

Full sun, ideally at least 6 hours daily; light afternoon shade can help in warm conditions.

Water

Keep soil evenly moist, providing about 1-1.5 in (2.5-4 cm) of water weekly from rain or irrigation, adjusted for soil and weather. Avoid drought followed by heavy watering.

Soil

Fertile, firm, moisture-retentive but well-drained soil, ideally pH 6.5-7.5. Work in well-rotted compost before planting.

Height

1.5-3 ft (0.45-0.9 m)

Spread

1.5-2.5 ft (0.45-0.75 m)

Flowers

If left unharvested, heads loosen and produce stalks of yellow flowers, usually in spring or summer depending on sowing time and climate.

Foliage

Large, thick, blue-green to grey-green leaves with pale, prominent ribs; inner leaves may partly cover the head.

Growth

Moderate; many varieties mature about 60-100 days after transplanting, while overwintering varieties take considerably…

Care needed

High

• Low allergen
• Edible

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Hard

Toughness

Needs looking after

Pick your zone, country, light and whether you have pets.

1. Planting day

   0.5 ft (0.15 m)

2. After 1 year

   2.2 ft (0.68 m)

   full size

Full size in one season.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Moderate

• Set young plants 18-24 in (45-60 cm) apart in firm soil; follow wider spacing if specified for your variety.
• Water at soil level before the root zone dries out, especially while heads are forming.
• Apply a balanced vegetable fertiliser before planting; feed again during leafy growth if soil fertility is low.
• Mulch around established plants to conserve moisture, keeping mulch away from the stems.
• Cover plants with fine insect mesh immediately after planting, securing the edges.
• For white varieties that do not cover themselves, loosely fold or tie outer leaves over the developing head to limit yellowing; leave room for air movement.

Pruning. No routine pruning is needed; retain healthy leaves because they feed and protect the head. Cut the firm, compact head with a short length of stem before its surface loosens, then remove the remaining plant because cauliflower does not normally produce a useful second crop.

Pick the main head when it is firm, compact and at the variety’s stated size, commonly 6–8 inches (15–20 cm) across, before the curds loosen or flower stalks appear. Quick varieties are often ready 2–3 months after transplanting; overwintering varieties take longer and are harvested the following spring. Cut the stem below the head with a sharp knife, leaving a few surrounding leaves to protect it;

Late winter

In cool climates, sow an early variety under cover about 4-6 weeks before the intended spring planting date.

Spring

Harden off seedlings and transplant while young and actively growing; protect them from hard frost and install insect mesh.

Late spring

Check beneath leaves for pests, maintain even moisture and mulch once the soil has warmed.

Summer

In cool regions, sow autumn-cropping varieties; protect seedlings from heat and do not let them become pot-bound.

Autumn

Harvest mature heads promptly. In mild-winter regions, including many parts of Australia, plant locally recommended varieties for winter or spring harvest.

Winter

Check overwintering crops for waterlogging and wind damage; use fleece during severe cold where the chosen variety needs protection.

• Plant in orderly blocks in a potager, using its broad blue-green leaves to contrast with fine-textured herbs.
• Use purple or orange-headed varieties as seasonal accents in an edible border.
• Place in accessible raised beds where watering, pest checks and harvesting are straightforward.
• Combine with short rows of lettuce or radishes that can be harvested before the cauliflower reaches full size.

Garden styles it suits: Potager (kitchen garden), Edible landscape, Homestead, Cottage garden, Farmhouse and Family-friendly.

Plant it with: Lettuce, Radish, Spring onion, Beetroot, Dill and Calendula.

Wildlife: Leaves feed cabbage white butterfly caterpillars and other brassica insects. Plants allowed to flower provide nectar and pollen for bees and hoverflies, although this sacrifices the edible head.

• Cabbage caterpillars: inspect leaf undersides and remove eggs and caterpillars; prevent egg-laying with well-secured insect mesh.
• Cabbage aphids: grey, waxy colonies gather on young growth and heads; dislodge small infestations with water and remove heavily infested leaves.
• Clubroot: swollen roots cause wilting and stunted growth; use clean transplants, improve drainage, avoid moving infected soil and keep brassicas out of affected beds for several years. Adjust acidic soil towards pH 7.0-7.5 after a soil test.
• Small, premature heads or loose curds: temperature stress, drought, checked growth or unsuitable varieties can spoil the crop; use locally recommended sowing dates, transplant young plants promptly and keep water and nutrients consistent.

Cauliflower heads, leaves and stems are not known to be toxic to people, cats or dogs; large amounts may cause gas or digestive upset. It is not generally regarded as poisonous to horses, but large quantities of brassicas are unsuitable feed and can cause digestive or other health problems.

• Broccoli (Brassica oleracea var. italica)

  Broccoli usually has a green or purple head with clearly visible bead-like buds and branching stalks; cauliflower forms a denser curd with much less distinct buds.

• Cabbage (Brassica oleracea var. capitata)

  Cabbage forms its head from tightly overlapping leaves rather than an exposed curd of immature flower tissue.

• Romanesco (Brassica oleracea Botrytis Group)

  Romanesco is a closely related cauliflower type with lime-green, pointed florets arranged in conspicuous spirals, rather than the rounded surface of most cauliflower heads.

Cauliflower comes through Italian cavolfiore, meaning 'cabbage flower', while the botanical epithet botrytis refers to a grape-like cluster.

Propagation. Grow from seed, usually in modules before transplanting. Choose varieties and sowing dates recommended for your climate; seed saved from flowering plants may cross with other flowering Brassica oleracea crops and may not come true.

Accepted botanical name

Brassica cretica cretica Brassica oleracea var. botrytis is an older name for Brassica cretica cretica.

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.