Ornamental cabbages and kales are nice plants for autumn and winter display but they tend to hover around the fringes of acceptance in gardens. While they are very tempting when at their finest in garden centres in autumn, they tend to disappoint once bought. Incorporated into patio pots, the plants tend to get scruffy over winter and then sprout and run to flower in spring. I actually like it when they do this and I quite like the mass of yellow, cruciferous flowers. But the plants are very different to what was bought and, of course, they then die. There is also the issue of growing a plant for ornament that is prone to a host of pests and diseases. While it is acceptable to grow a cabbage under ‘insect mesh’ to keep off the butterflies and aphids but it is a bit pointless when you are growing the plant for ornament.
But are these plants edible? All cabbages, sprouts, kales, cauliflowers, collards etc are Brassica olearacea, and they are all edible. Most of us have different opinions about what is edible. I don’t consider oysters to be edible (how hungry was the first person that cracked open an oyster shell and decided that was they found inside looked tasty!). Lots of people would disagree with my opinion that Brussels sprouts are edible. But ornamental kales and cabbages are edible. They are bred for looks rather than taste or tenderness so they may not taste the best but they are edible. The fact that they are frequently brightly coloured actually adds to their nutritional value.
An important caveat is that if you buy a colourful kale in a pot or have a bunch of flowers containing tall-stemmed colourful cabbages it is best not to eat them. This is not because the plants are intrinsically inedible but because they may have been grown with pesticides or treated with chemicals post-harvest. If you had grown these yourself it would be OK to eat them.
Plant breeders have been busy creating new edible/ornamental kales and other brassicas and these are really pretty exciting. Not only do they brighten up the veg plot, they are very nutritious and delicious.
The first of these was ‘brukale’ or ‘kalettes’ which are a cross of Brussels sprouts and kale. The plants grow like Brussels sprouts but the sprouts are replaced with feathery ‘mini-kales’ in deep green or purple/green. I have found plants are very vigorous and they are very good but if you get mealy aphids on the plants then they get into the mini-kales and nothing edible is produced. I also tend to prefer the ‘kalettes’ when they start to sprout in spring rather than when they are tight rosettes. It goes without saying that these cost a lot if you buy them in shops.
The next generation of colourful kales is not being produced and I have grown the pink ‘Midnight Sun’ and white ‘Emerald Ice’, both pretty and tasty non-heading cabbages or frilly kales. Even brighter is the pink ‘Rainbow Candy Crush’.
Should you grow them? Well it depends on how you eat your kale. If you only eat it cooked I would suggest that green is best. From bitter experience I have learned that cooked, strangely coloured food is not actually very appetising. Pink kale leaves in salads are fine but not so much when boiled and leaking pink juice into mash. Conversely, they may be better than green in smoothies. I think we should encourage the development of new forms of brassica, after all they are nutritious and can be grown locally.
So, briefly, ornamental cabbages are edible but only eat them if they have been grown for eating and are not treated with chemicals, which they may be if they are grown to look at rather than to eat.