How to Grow Kale in the UK – Sowing, Care and Harvest Guide

Kale is the most reliable winter vegetable in the UK kitchen garden. While other crops have finished and the beds are bare, kale stands through hard frosts, driving rain and the bleakest months of a British winter, producing fresh leaves continuously from November through to April. It is extraordinarily nutritious, genuinely cold-hardy to temperatures well below freezing, and – a fact that surprises many first-time growers – it tastes significantly better after frost, which converts the starches in the leaves to sugars and mellows the flavour in a way that warm-season leaves cannot match.

Kale is also one of the simpler brassicas to grow compared to cauliflower or Brussels sprouts, which have narrower timing windows and more exacting soil requirements. Kale tolerates a wider range of conditions, grows vigorously from transplants, and does not require the firm, deeply cultivated soil that its brassica relatives demand for the best results. The main challenges are the same as for all brassicas – keeping the caterpillars and pigeons off through the growing season – and both are manageable with netting and vigilance.

Choosing a variety

Dwarf Green Curled is the standard recommendation for most UK kitchen gardens and is the right starting point for anyone new to growing kale. It stays compact at around 45-60cm, makes the most efficient use of bed space, and produces the tightly curled leaves that work well both raw and cooked. Cavolo Nero – the tall, dark, strap-leaved Italian type also known as Black Tuscany or Lacinato kale – is the variety favoured for cooking, particularly for braises and pasta dishes, where its dense, blistered leaf texture holds up well to heat. It grows taller than Dwarf Green Curled and needs more space, but the flavour is exceptional. Red Russian is the mildest of the common types and is the best choice where kale will be eaten raw in salads – its flat, tender leaves are far less fibrous than curly types when picked young.

Sowing and planting out

Kale is almost always started in modules or a seedbed and transplanted rather than direct-sown where it is to grow. Sow into module trays or small pots from March to May, planting two seeds per cell and thinning to one seedling once both have germinated. Cover with 1cm of compost and place on a windowsill or in a cold greenhouse – no heat is needed for germination, which occurs reliably within seven to ten days at most UK spring temperatures. Grow the seedlings on until they are 10-15cm tall with a firm root system before planting out, which typically means five to six weeks from sowing.

Plant out from May onwards, once the risk of hard frost has passed and the plants are large enough to withstand slug damage. Space plants 45cm apart for dwarf varieties and 60cm for taller types like Cavolo Nero and Redbor. Kale benefits from being planted slightly deeper than it sat in its module – burying the stem up to the first true leaves gives the plant a more stable anchor, which is valuable for a crop that will stand through winter gales. Firm the soil around each plant thoroughly with your foot after planting and water well. A collar of brassica root fly barrier fabric around each stem base at planting time prevents the cabbage root fly from laying eggs in the soil around the roots.

Spacing, staking and care

Kale is a hungry crop that benefits from a fertile, well-prepared bed. Incorporate well-rotted compost or manure in the autumn before planting, and rake in a general granular fertiliser at planting time. A top-dressing of a nitrogen-rich fertiliser in late summer – when the plants have established but before autumn growth begins – encourages the strong leafy growth that will be harvested through winter. Do not overfeed with nitrogen in spring or early summer, which produces lush, soft growth that is more susceptible to pest damage.

Taller varieties need staking by autumn – Cavolo Nero in particular can reach 1 metre or more and becomes top-heavy through winter. A single bamboo cane per plant and a figure-of-eight tie around the main stem is sufficient. Check and adjust ties after storms. Dwarf varieties are generally self-supporting but may need individual canes in exposed sites. Netting over the entire brassica bed with fine mesh or purpose-made brassica netting is the single most effective cultural measure for the whole season – it excludes cabbage white butterflies and pigeons simultaneously and can remain in place from planting until harvest.

Seasonal care calendar

Harvesting and using kale

Kale is harvested by picking individual outer leaves rather than cutting the whole plant. Always leave the central growing point and the youngest inner leaves in place – these are what the plant will continue to grow from. Take no more than a third of the leaves at any one picking, working around the plant and taking the oldest, outermost leaves first. Picked this way, a single plant provides a continuous harvest over five to six months rather than one single cut.

The young side shoots that appear from late February onward as the plant begins its second-year growth are one of the most delicious harvests in the winter garden. These 10-15cm shoots – similar in character to sprouting broccoli – are tender, mild and sweet, and should be picked before the flower buds open. Keep picking them regularly to extend the flush as long as possible, usually into April. Once flowering begins in earnest and the shoots become too small and fiddly to bother with, remove the plants and prepare the bed for summer crops.

Common problems and solutions