Plant kale.

Like it or not, curly kale is a cracker of an easy winter crop and like parsnips and swedes tastes much better after the first hard frosts. Incidentally, the thicker leaves of ‘Blue Ridge‘, ‘Squire‘ and ‘Scotch Blue Curled‘ (all from Kings Seeds) seem less afflicted by white cabbage butterfly caterpillars than the more delicate raggedy foliage of ‘Red Russian‘ or Italian cavolo nero.