Caring for cabbages
Val has a few tips on protecting brassicas from butterflies
IT’S always swings and roundabouts when you’re growing vegetables, because some things fail to thrive. This year the beetroot didn’t plump up, due to the extreme early heat, and I lost most of the sweetcorn to a savage late frost because I didn’t wait until the first week of June before planting it out. Lesson learnt! It’s been too windy up here for the runner beans, so we have picked only a few pounds so far.
Other things have done well, though. We have harvested countless lettuces, more than 30 cucumbers, 42lb (19kg) of tomatoes, 22lb (10kg) of courgettes, 16lb (7kg) of peas, 32lb (14kg) of new potatoes and almost 20lb (9kg) of broad beans from the 8x4ft (2.4x1.2m) plots in our garden.
The trouble is that summer produces a glut of some vegetables, and if the Best Beloved makes me Jamie Oliver’s courgette carbonara again I may scream – ungrateful as it is! I prefer my winter pantry of vegetables by far and I rely on parsnips, leeks and brassicas for sustenance. I can pick them throughout winter, a little at a time, or better still, send the Best Beloved out to do the job.
Stored onions, winter squashes and borlotti beans are the other staples.
Parsnips, which are notoriously difficult to germinate, came up like cress this year due to a warm and sunny spring. I use an F1 variety called ‘Gladiator’ and I also sow an F1 leek called ‘Oarsman’. Both Britishbred Tozer Seeds’ varieties germinate well because they have hybrid vigour. My tip is always water the drills and sow them on still, ambient days.
The real winter staple is the brassicas and I raise black Tuscan kale, which can be picked from October onwards. I’m careful not to overpick this in autumn, as denuded plants often perish in cold winters. I grow hearting winter cabbages, including a few red cabbages, Savoys and winter cabbages. I also grow purple sprouting broccoli and a few Brussels sprouts. These provide food from October through to April, if I can keep those dastardly white caterpillars away!
I have to net my brassicas against small white and large white cabbage butterflies, because we get so many here. Inevitably some get through the netting, so a regular watch is kept. The small whites, the most adept at finding gaps, only lay a single egg. The resulting green caterpillar gets into the heart of cabbages, but is far less damaging than the large whites’ clusters of green and yellow caterpillars that can wreck a brassica plant in hours.
Adult butterflies seem able to find the tiniest hole and I spend a lot of time chasing them off, or clapping my hands.
We’re on constant alert for newly emerged clusters of large white caterpillars, although I have to put on gardening gloves before I rub them off. It’s a girl thing…
This year whitefly have been more of a problem than usual. However, we’ve had help from our resident wasps. They’ve been flying through the netting and taking whitefly and tiny caterpillars away in their jaws.
Birds would also take these tiny cabbage-eating caterpillars if they could get through the netting. However, birds don’t eat the more mature caterpillars as the caterpillar bodies are too full of bitter mustard oil from the digested foliage of the brassicas. Even after the caterpillars have gone, we have to keep the netting on otherwise the pigeons would feast upon the leaves in cold weather.
There is a predator of cabbage white caterpillars, a small parasitic wasp called Cotesia glomerata. These wasps lay their eggs in newly hatched caterpillars and, after many weeks, the caterpillar’s body ruptures to reveal sulphur-yellow cocoons that look like insulation. This happens in autumn and you often see this pallid-yellow cotton wool-like mass in greenhouses and sheds. New parasitic wasps will emerge in spring, from the dead caterpillar’s body.
I need as many as I can get.