Fertilizer Insects Diseases Cole crops, which include broccoli, brussels sprouts, cabbage, cauliflower, and kohlrabi, can be successfully grown on most soils if drainage is good and the crop is supplied with adequate water and nutrients, particularly nitrogen. Light-textured soils usually produce earlier crops but heavier soils hold more moisture and tend to produce crops that hold quality longer at maturity. Cole crops have shallow root systems. Inadequate moisture may cause small cauliflower heads to form prematurely. Rainfall or irrigation following a prolonged dry spell may cause splitting of cabbage and kohlrabi.
Supplemental irrigation is important for growing cole crops in Nebraska.
Broccoli and cauliflower can withstand light frosts. This can be a particular problem in broccoli and cauliflower. Cabbage is the most heat tolerant, but prolonged high temperatures cause puffy heads with long cores and increased tipburn. Quality deteriorates and plants develop bitter flavors and a tough texture. Young plants can tolerate colder and warmer temperatures than older plants.