When to plant cabbage

Head cabbage comes in types for every season, and the type decides the timing. Early and pointed cabbages are sown indoors in February or March and planted out from late March or April under fleece. They are ready from early summer.

Summer and autumn cabbages are sown from March to mid-May and planted out from mid-May into June. They take about 20 weeks from sowing and are cut from July to October.

Storage white cabbage, red cabbage and savoy go in last: sow in April or May and plant out in June. Savoy and winter cabbages stand in the bed from October into winter, while white and red storage heads are cut in autumn and kept.

Don't rush the earliest plantings. A long cold spell after planting can make young cabbage bolt instead of forming a head. Wait for milder weather and cover early plants with fleece.

Sow 0.4–0.8 in deep in modules, small pots or a seedbed, a couple of seeds per spot, and keep the strongest. Seedlings come up in one to two weeks. They are ready to plant after about five weeks, at 4–6 in tall with five or six true leaves.

Choose a sunny spot with deep, fertile soil. Work in about two buckets of compost per square metre, check the pH and lime acid soil: around 7 suits cabbage and keeps clubroot at bay. Then tread the bed firm: all brassicas like a solid footing.

Plant each seedling a little deeper than it grew, up to the lowest leaves, firm it in and water well. Space early and pointed cabbages 12–16 in apart and big storage heads and savoy 18–20 in apart, with 20–24 in between rows. Closer spacing gives smaller heads, which can be handy for a small household.

A 120 × 80 cm raised bed takes four large cabbages, or up to eight small early ones.

Cabbages are Starkzehrer, heavy feeders. On good soil the compost you dug in carries them a long way. Once the plants have settled in, and before they start to form hearts, give a nitrogen-rich organic feed if growth looks pale or slow. Don't overdo it: soft, lush growth attracts aphids and caterpillars.

Water in dry spells, generously rather than a little every day; roughly every ten days is enough in most summers. A mulch keeps the soil moist between waterings. Keep weeds down while the plants are small.

Cut a cabbage once the head feels firm when you press it. Size depends on the variety and on how closely you planted. Cut the stalk just above the lowest leaves.

With early and summer cabbages, cut a shallow cross about 0.4 in deep into the stump that is left. It often sprouts a few small second heads a few weeks later.

Heads for storing should be cut as late as possible in autumn, when dry and without damage. Kept cool, dry and frost-free, on slatted shelves or hung up, late white and red cabbage lasts for several months; close to 32°F with high humidity, up to about five. Summer cabbage keeps a week or two in the fridge.

Savoy and winter cabbages are very hardy and can simply stay in the bed until you need them.

White cabbage makes dense, smooth heads and is the one for sauerkraut and coleslaw. Late varieties store best. Red cabbage is grown just like it and also stores well.

Savoy has crinkled, blistered leaves and a looser head. Along with winter cabbage, it is the one to leave outside and cut from autumn into winter. Pointed cabbage (Spitzkohl, 'Hispi' in the UK) is quick, tender and ideal for early crops.

If clubroot is already in your soil, clubroot-resistant F1 varieties such as 'Kilaxy', 'Kilaton' or 'Kalibro' are worth a look.

Cabbage white caterpillars are the classic cabbage pest. They feed from about May to October, and some bore right into the heart of the head. Check the leaf undersides every week, squash yellow egg clusters and pick off caterpillars, or keep the butterflies away with mesh.

Cabbage root fly lays eggs at the stem base from late April onwards. Its white maggots eat the roots, and young plants wilt and die, most often after the first generation in late spring. Fit a collar 3–6 in across snugly around each stem at planting, or cover the bed with mesh.

Insect mesh laid straight after planting is the most reliable protection. Holes of about 1.3 mm keep out cabbage whites and root fly; 0.8 mm also stops flea beetles and mealy cabbage aphids. Bury the edges and lift the cover only briefly, for weeding.

Slugs, pigeons, mealy cabbage aphid and cabbage whitefly also like cabbage. Remove the first aphid colonies as soon as you see them, and hose whitefly off the leaf undersides.

Clubroot is the serious one. Roots swell into solid, distorted clubs, and the plants wilt in warm weather and stay stunted. The spores last in soil for many years, up to 20. Lime to around pH 7, raise plants in pots so they go out with a strong root ball, bin infected roots, and wait at least four years before cabbage-family crops return to a bed; after an outbreak, seven or more.

Cabbage belongs to the cabbage family (Brassicaceae), with kale, broccoli, cauliflower, kohlrabi, Brussels sprouts, radishes, turnips and rocket. All of them count for rotation, and so does mustard sown as green manure.

Mixed-planting charts put cabbage next to celery, tomatoes, lettuce, spinach or beans, sometimes claiming that the smell of tomatoes or celery keeps cabbage whites away. We found no good evidence for that; treat these pairings as tradition.

What is backed by research: a low living mulch of clover between brassicas hides them from cabbage root fly, which looks for plants standing in bare soil. Mixed plantings generally carry fewer pests than a bed of one crop.