We nearly always recommend that you net any brassicas – kale, broccoli, cabbages, cauliflower etc – in your plot using a mesh netting. This will help to keep butterflies from laying their eggs on leaves, and thus protecting brassica plants from caterpillars. It will also help to protect brassicas from pigeons, which will easily demolish an entire row of kale in a few minutes!
As we come into the heart of autumn in mid October, and then towards winter, you won’t see many butterflies flitting around, and may be wondering whether or not the netting is needed.
Butterflies will be back in spring, so you’re wise to net all brassicas in April/May through to October/November. Over winter, you won’t need to worry about them. But you will need to worry about pigeons…
Pigeons are active all year round, however they are not as interested in mature plants. If you’re growing cabbages or broccoli that you planted in spring this year, then they will probably be fine without any netting now – this means that you can use the netting on younger, newly planted brassica plugs which DO need protecting against pigeons.
If in doubt, and if you have enough netting, then just keep them netted! But, if you’re short on netting, then you can take a risk and use it just on the younger seedlings.