Red Cabbage
Brassica oleracea var. capitata f. rubra
Slower and denser than green, keeps longest, and turns blue if you cook it without acid.

Slower, denser, better keeping
Red cabbage takes two to four weeks longer than a comparable green variety and forms a noticeably denser, heavier head. That density is why it stores three to four months - longer than any other cabbage - and why it takes longer to cook.
The colour chemistry matters
The anthocyanins that make it red are pH-sensitive: cooked in alkaline or neutral water they turn an unappetising blue-grey. Add vinegar, lemon juice, wine or apple at the start of cooking and it stays red. This is not a garden problem but it is the thing everyone discovers the hard way.
Start indoors, transplant
Sow indoors four to six weeks before setting out. Given the long season, an early spring start for a summer crop or a June sowing for autumn both work; autumn crops have better flavour and fewer pests.
Heavy feeding and near-neutral pH
Rich soil with plenty of compost, nitrogen side-dressings every three to four weeks. pH 6.5-7.5 - lime acidic soil, which also suppresses clubroot.
Even water
Dense heads split readily when heavy rain follows drought. Consistent moisture and a mulch. A plant about to split can be twisted a quarter turn to break some roots and slow uptake.
Pests
Cabbage worms are somewhat less of a problem on red cabbage than green - the caterpillars are conspicuous against the purple leaves and are easier to spot and pick, and there is some evidence they prefer green varieties. Row cover from transplanting is still the best control. Cabbage root maggot, aphids and flea beetles as usual.
Clubroot and rotation
Rotate brassicas on four years. Clubroot causes swollen distorted roots and persists in soil for a decade; high pH suppresses it.
Harvest and storage
Cut when firm and heavy for its size, leaving outer leaves. Store whole and unwashed at just above freezing with high humidity for three to four months. It also makes excellent long-keeping pickled cabbage and sauerkraut.
- Days to harvest
- 90-120
- Spacing
- 18-24 in
- Row spacing
- 24-30 in
- Sun
- Full
- pH
- 6.5-7.5
- Head
- Very dense
- Storage
- 3-4 months
- Cooking
- Needs acid to hold colour