As the year starts to move towards autumn, it’s time to think of planting brassicas (cabbage, cauliflower, broccoli and kale) for winter. They need to be in the ground for several weeks before the cold weather hits, or they will sulk all winter and then run to seed when the weather warms up.
On the other hand, while there’s still some warmth in the sun, white butterflies will be looking for somewhere to lay their eggs. To stop the butterfly caterpillars from reducing your plants to woebegone tatters, you can cover them with something like quarantine netting. You’ll need some kind of hoop or arch to hold the cloth, depending on how big your plot is. You can bend plastic pipe into the right shape or buy cloth-covered cloches.
Brassicas appreciate plenty of manure, which should be well rotted. Healthy plants are less likely to be attacked by pests, and the more fertile the soil, the healthier the plants will be. Once the weather is colder, the white butterflies will disappear, but then you need to be on the watch for slugs and snails. Use a beer trap or a snail bait that is not toxic to birds.