Introduction
Cauliflower is a versatile vegetable, prized for its large, edible white curds. It’s a bit finicky to grow but well worth the effort for its unique flavour and nutritional benefits. Growing cauliflower in the southeast UK can be successful with the right care and attention.
Why grow cauliflower?
Cauliflower is rich in vitamins C and K, fibre, and antioxidants. Homegrown cauliflower often has superior flavour and texture compared to store-bought varieties. Growing your own ensures that it’s free from pesticides and can be harvested at peak ripeness.
Suitability for different growing environments
Cauliflower prefers cool temperatures and can be grown in the ground or raised beds. It thrives in fertile, well-drained soil with a pH between 6.5 and 7.5. Consistent watering and a stable environment are key to preventing the plants from bolting or producing small heads.
Lifecycle
Cauliflower is a biennial plant usually grown as an annual. It takes about 16-18 weeks from sowing to harvest, depending on the variety and growing conditions. Sowing is typically done in early spring, with a second sowing possible for a late autumn harvest.
Sowing and harvesting periods
- Sowing: Indoors from February to April, outdoors from April to May
- Transplanting: 4-6 weeks after sowing, when seedlings have 2-3 true leaves
- Harvesting: June to October
Recommended varieties
Popular cauliflower varieties for the UK include:
- ‘All Year Round’
- ‘Clapton’
- ‘Romanesco’
- ‘Cheddar’
How to sow
Start seeds indoors in modular trays 6-8 weeks before the last frost date. Sow seeds ½ inch (1.25 cm) deep in seed compost, and keep the trays at 60-70°F (15-21°C). When seedlings have 2-3 true leaves, they are ready for transplanting.
How to prick out/pot on
Transplant seedlings into larger pots when they are 3-4 weeks old, ensuring they have enough space to grow strong roots. Harden off seedlings by gradually exposing them to outdoor conditions for 7-10 days before planting out.
Where to plant
Choose a sunny or partially shaded spot with fertile, well-drained soil. Enrich the soil with plenty of organic matter, such as compost or well-rotted manure, before planting. Avoid planting cauliflower in the same spot as other brassicas from the previous year to prevent soil-borne diseases.
How many to plant (spacing)
Space cauliflower plants 18-24 inches (45-60 cm) apart in rows 24-30 inches (60-75 cm) apart. This spacing allows for adequate air circulation and room for the plants to develop large heads.
How to plant
Plant seedlings deeply, burying them up to their first set of leaves. Water well after planting and mulch around the plants to retain moisture and suppress weeds. Adding a layer of mulch also helps keep the soil cool.
Protecting your plants
Cauliflower can be susceptible to pests like cabbage root fly, slugs, and aphids. Use horticultural fleece or fine mesh to cover young plants and protect them from pests. Handpick slugs and snails regularly, and use organic slug pellets if necessary.
How to feed and water
Cauliflower needs consistent moisture to form good heads. Water regularly, especially during dry spells, to keep the soil evenly moist. Feed plants every two weeks with a high-nitrogen fertiliser to promote strong growth and head formation.
How to propagate, prune/manage while growing
Cauliflower is typically grown from seed, but you can also propagate by division if you have a variety that produces side shoots. Pruning is not necessary, but you should remove any yellowing or damaged leaves to maintain plant health. When heads start to form, tie the outer leaves over the heads to protect them from sun and keep them white.
How and when to harvest
Harvest cauliflower when the heads are firm and compact, usually 7-12 inches (18-30 cm) in diameter. Cut the head from the plant with a sharp knife, leaving a few outer leaves to protect it. Harvest promptly to avoid the head becoming loose or yellowing.
How to store
Cauliflower can be stored in the refrigerator for up to two weeks. Wrap the heads in a damp cloth or place them in a perforated plastic bag to maintain freshness. Cauliflower can also be blanched and frozen for long-term storage.
How to eat/cook
Cauliflower is incredibly versatile in the kitchen. It can be eaten raw in salads, steamed, boiled, roasted, or used in soups and stews. It’s also popular as a low-carb alternative to rice or mashed potatoes.
How to deal with pests and disease
Common pests include cabbage root fly, slugs, and aphids. Use row covers to protect young plants and encourage natural predators like ladybirds and lacewings. Practice crop rotation to reduce the risk of soil-borne diseases such as clubroot and downy mildew.
When and how to remove the plants
Remove plants after harvesting by cutting them at the base and composting the remains. Clear the bed of any debris and prepare the soil for the next crop by adding compost or well-rotted manure.
What to plant before and after
Good preceding crops for cauliflower include legumes like peas and beans, which fix nitrogen in the soil. Root crops like carrots and beets are also suitable. After harvesting cauliflower, plant nitrogen-fixing crops like peas or beans to replenish the soil. Alternatively, grow leafy greens like spinach or lettuce, which will benefit from the rich soil.
What to interplant with
Cauliflower can be interplanted with fast-growing crops like lettuce or radishes, which can be harvested before the cauliflower needs the space. Companion plants like dill and chamomile can also help deter pests and attract beneficial insects. Avoid planting cauliflower near other brassicas to reduce the risk of disease.