Next year, it will be different. As if we really could control nature...although Gardeners' World suggests a thorough spray of bacillus thuringiensis above/below the leaves to prevent the cabbage white caterpillars. Will give it a go next year before the onslaught! I'm forever picking them off by hand these days and squishing underfoot; I'm sure by the looks of the plants, I'm only getting a few among the legions of these creatures. First time posting on this lovely site and it's a grumble...