For the last few years growing Cavalo Nero – otherwise known as Tuscan Kale, I’ve kept it, along with other tall brassicas, under netting more or less all year round to fend off pigeons. I’m re-assessing this strategy now after a couple of seasons of whitefly infestations which have rendered the crop almost inedible without a considerable amount of washing and blanching in boiling water. Sowing the seed later has had some mitigating effect but not enough. Other Cavalo Nero plantings on the same allotments and grown without netting show very little whitefly on the underside of the leaves where they normally collect.

I suspect that the netting is also preventing the natural predators of whitefly from reaching the plants thus allowing them to breed without check. With a three week lifecycle this means a lot of whitefly over the summer! I’ve probably been over concerned about the damage caused by pigeons to this particular crop so next year the covers are coming off once the plants are big enough.

After taking off the covers, a few weeks ago the whitefly are now significantly fewer.