Kale
Brassica oleracea var. Acephala
Kale is loose-leaf cabbage, in many shapes and colours. It has been around since Roman times or before.
Introduction
Kale is loose-leaf cabbage, in many shapes and colours. This reflects in the name ‘Acephala‘, which means without head, contrasting to the cabbage group ‘Capitata‘, with head.
Kale has been around since Roman times or before. Its ability to stand temperatures below even -10° C/14° F makes it a valuable winter staple. On the other hand, kale plants struggle in excessive summer heat. This reflects their coastal origins.
Harvest period
- Days from seed to first harvest: 50 for salad leaves, 70 for cooking
Kale seeds sownKale ready to harvestEarly springThrough summer, autumn, perhaps winterEarly summerLate summer to spring, depending on winterLate summerWinter to spring, best under cover
- Best climate is moist, temperate, cool rather than hot. It grows a little in mild winters and survives cold ones.
Why grow them
I bracket kale with chard, as a super-reliable vegetable banker, although with more pests. At almost any time in a long growing season, you can harvest a few leaves of kale. There are not many new ones in the winter, but each one is precious. Every winter harvest feels special.
Choose from the many different varieties in a seed catalogue, whose variations include all these possibilities:
- Leaves good for salad or cooking
- Leaf colour from green to crimson
- Texture from smooth to curly
- Either productive green or less productive ornamental
- Harvests from tall plants, or short ones
- Spring harvests of small shoots with flower buds, similar to broccoli
Homegrown kale has stronger flavours than bought kale and excellent nutrition. Vitamins C and K, for example, are at a maximum in fresh leaves, which also boast 3% protein.
Eat raw and cooked
You can prepare kale in so many ways.
- If you like it raw, grow tender flat-leaved varieties such as Red Russian and the Ethiopian types, also Sutherland from Scotland.
- Roasted kale tastes exotic, partly depending on how much oil you add – a high amount results in kale crisps.
Most kale leaves have a fibrous stalk up their middle. Simply cut off the two tender sides and discard the stalk for compost.
Pattern of growth
You can grow kale as an annual plant, sown in spring and removed in the autumn. It is in fact biennial and flowers in the second spring, as long as it survives winter. The flowering shoots are super tasty, like mini broccoli.
There are a few varieties of perennial kale. This term causes confusion when sometimes misapplied to varieties that are slow to flower and behave with a perennial tendency. See the photo of Oisin Kenny in Galway, Ireland – the last photo at the end of the lesson.
True perennial kale does not flower and therefore makes no seeds. As a result, it is propagated from stem cuttings, an easy process that takes only a few weeks.
If you don’t have stems, you may be able to buy a rooted plant, grown from a stem.
Suitable for containers/shade?
Kale tolerates shade, though best to plant in the sun.
For growing in containers, select a dwarf variety. Dwarf curly kale, for example, is nicely compact and its small size means that it won’t be diminished by a restricted root volume.
Kale’s rapid rate of growth and continual harvests do come at a price. They have a great need for moisture and, after the initial flush of growth, you need to feed plants in containers (though not in beds).
Varieties
Cavolo Nero, or Black Cabbage and Tuscan kale, grow dark green, long leaves, on plants of varied height according to the seed supplier. The leaf texture is savoyed.
Kalettes are half kale and half Brussels sprouts, a modern hybrid. Tall and vigorous plants grow large harvests in the dead of winter. They are super tasty – pigeons love them too!
Taunton Deane kale plants, rooted and ready to be transplanted, with broad-leaved sorrel at the back
Lerchenzungen (‘Lark’s tongue‘) is perhaps the German equivalent of Tuscan kale with long leaves, except that they are curly and lighter green. An equivalent variety with broader leaves is Westlandse.
Hungry Gap grows its green, mostly flat leaves for longer in spring, before flowering quite late in spring.
Ethiopian kales are flat-leaved and tender, good in salad. Also, they flower in the first year so the harvest period is short, in a temperate climate at least.
Dwarf Curly and Dwarf Red Curly grow as named, into bushy plants with leaves better cooked than raw.
Sutherland is a tall, green flat-leaved kale with tender leaves.
Red Russian (‘Ragged Jack’) has lovely pink tinges to its green, serrated leaves. They are tender raw, and the flower shoots in spring are especially prolific and tasty.
Red Devil has lovely red stalks in smooth and tender leaves, on small plants.
Thousand Head does indeed make several stems from one plant – not so good if you want large leaves. However, in spring it’s excellent, with many tender shoots from one plant.
Redbor and Darkbor are dark red, tall hybrids.
Scarlet kale is not a hybrid, less tall and a little less crimson.
Recently, breeding has worked to create gorgeous colours. Candy Floss and Emerald Ice look amazing and taste good.
Taunton Deane is a tall perennial kale, possibly discovered in Somerset. Plants can continue to grow for more than a decade. It has now been nine years since I rooted the small stem of my oldest plant – the photo below shows you its reclining, stable posture.
Daubentons is a French perennial, mostly under 1 m/3.3 ft high and with many stems, plus smaller and slightly more tender leaves than Taunton.
Clear
Clearing usually happens in spring. Before that, you can enjoy the tender flowering shoots, equivalent to small broccoli, until in time they become thinner and more fibrous.
The thick main stems are best twisted round and round, until most roots have snapped off and remain in the soil. Or use a sharp spade to cut around the base of stems.
Prepare and plant
For all winter brassicas, I recommend adding compost for the year ahead during winter, while they are still growing, and up to six months before final clearing. Here are the advantages:
- It’s easy with kale because the cropping leaves are well above soil level and plants are widely spaced.
- Soil organisms are nourished through winter and protected from extremes of weather.
- Spread 2.5 cm/1 in of compost any time from mid-autumn. If it happens to be lumpier than usual, that is fine, because weather softens lumps before spring.
- In spring, the turnaround time is quick, between clearing kale and starting another vegetable.
Follow with
There is little ground preparation, except to walk on the beds if you had to lift soil when removing each plant.
Kale’s finishing time in spring means you can follow with any other vegetable – perhaps not a brassica, although it’s possible.
