When something goes wrong in the garden, it's wise to ask why. When something goes unexpectedly right, the same question is in order. Take bulb fennel, also called Florence fennel. One is told that bulb fennel is a cool-weather plant best grown as a fall crop, because warm weather makes it bolt -- that is, go to seed and fail to make bulbs. But since it's also frost-sensitive in fall, and the bulbs keep poorly in storage, that season is disappointingly short. So at our place we grow a spring crop as well.