Q.why no heads in my cabbage?
I planted purple cabbage in Dec. in my garden in San Jose, CA. The plant looks very healthy with huge leaves. It is trying to produce head but I see no head formation. Can it be due to the very warm weather?

Certified GKH Gardening Expert
Yes, warm weather can cause problems with heads forming. You can try shading the plant some or mulching the roots and extra water may help as well.
This article may be helpful:
https://www.gardeningknowhow.com/edible/vegetables/cabbage/cabbage-head-formation.htm