Kale has had a bad press for a long time. Goodness knows why, although it’s reputation as a poor man’s vegetable hasn’t helped. It’s also fed to cattle, which never does much for a veggie’s image. I’m delighted that it’s undergoing a renaissance.
It started a few years ago when the dark, dramatic Cavolo Nero appeared in seed catalogues, and since then more and more varieties have been released. This is particularly good for potagers, where the enormous variety of colours and leaf shapes offered by kale add character to the mixed borders.
Why Grow Kale?
You shouldn’t be without kale for a whole host of reasons. First, it suffers less from pests than most brassicas. I gave up growing cabbage some years ago, worn down by the constant battle with pigeons and caterpillars. While kale isn’t immune from their attentions, it appears much less attractive and, being in effect a loose-leaf cabbage, damage to a few leaves has much less impact on the whole plant than, say, a rapacious caterpillar in the centre of a drumhead cabbage. The curly-leaved varieties withstand the cabbage white butterfly’s attention best, probably because its leaves make it harder to lay eggs.
The advantages don’t stop there. Decorative and pest-resistant, kale needs very little attention, is very hardy, and actually improves in taste with frost. Plants can be harvested almost continuously (growth does slow down in the darkest months) and I’d aim for 8-12 plants for a good continuous supply. They last throughout the winter, produce leaves early in the spring and, when they eventually start to produce flower buds, these too can be eaten before they open, like broccoli.
When not to Grow Kale
I’ve never, sad to say, lived in a very hot climate, but general advice is that kale prefers cooler temperatures (60-70°F, 15-21°C), and although it will tolerate drought and hot weather, both will affect its quality and can encourage bolting. It does, however, tolerate partial shade and, if you do live in a hotter climate, you may like to try it in shadier spots, but heat can make kale taste bitter and collards are recommended for warmer areas.
How to Grow Kale Like an Expert
Seed packets may tell you different, but I wouldn’t bother sowing kale until late spring (May and early June in the UK) or even early summer. Ideally, you want well-drained soil that nevertheless remains moist, so it’s a good idea to mulch around the plants.
When I first started gardening I thought that kale had to be transplanted, as all the instructions told you to do so. You don’t. It can be sown in situ (if you do this, then thin the kale gradually to the final recommended spacings – thinnings can be used in salads or stir fries).
The reason it’s often transplanted is to allow room for earlier vegetables in the kale’s final planting space (easy to organise using our Garden Planner’s succession planting feature). In a typical crop rotation sequence, it can follow on from early peas, early potatoes, broad beans and lettuces, even French beans.
If sowing into the ground, rather than in pots, sow thinly about a half inch deep (1 cm), in rows six inches (15 cms) apart. As they grow, thin to around 3 inches (7.5 cms) apart.
Transplant when the seedlings are around 4-6 inches (10-15 cms) tall (generally around a month after sowing) and place them 14-20 inches (35-50 cms) apart (depending on whether you’ve chosen a dwarf or full-size variety) in rows 18 inches (45cms) apart. Bury the stems up to just below the level of the lowest leaves. Tread the soil down around the base of plants firmly and continue to do this from time to time, to prevent any "wind-rock" as they grow.
I start harvesting when the plant is around 18 inches (45 cms) high and has reasonable sized leaves, but you could start earlier (but gently) for salads and stir fries. Take a few leaves at a time from each plant. If you remove the head (which I normally do in late autumn, then side shoots start to develop. These are great when eaten young, about 5 inches (12cms) long.
Home-grown kale, lightly steamed and drizzled with fresh lemon juice is wonderful and with so many varieties to explore I hope you'll agree that kale is well worth finding space for in any garden!