Now's the time to harvest your cauliflower if you used a polytunnel to get a couple of weeks ahead. If you don’t harvest the cauliflower as soon as it is ready it will continue to grow and the florets will begin to open spoiling its eating quality. Some varieties stand longer than others, so check the description in a seed catalogue. Below is a great recipe to use once you have harvested your cauliflower.
http://www.bbcgoodfood.com/recipes/2638/cauliflower-tempura