I previously asked why my plants were not forming heads. I do have them mulched, and the plants are not oversized. The broccoli, which is right next to the cauliflower, did amazingly well. Is it too late in the year to expect the cauliflower to do anything?
Is It Too Late for Cauliflower to Form Heads?
Certified GKH Gardening Expert
It is not so much the time of year, but the heat of the year. In many parts of the country, it has been incredibly hot and even with mulching and watering well, the soil may just be too warm for the plants to form a head. I would not give up on them until they bolt. If they can get past this hot part of the summer without bolting, they may still form heads in the fall when it cools down.