This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
Broccoli, which is a long-season cauliflower, is in all respects like cauliflower except that its vegetative parts are somewhat coarser, the heads somewhat smaller, and it does not form an edible curd early in its life as does cauliflower.
Broccoli is cultivated only in climates having a mild winter, when it can be planted the summer before and carried through the winter to form heads early the following spring. It is a popular plant in all parts of France and particularly in England. It is undoubtedly the parent type of the cauliflower, the cultivated varieties of cauliflower being short-season forms.
For best results, the seed should be sown at the same time as that of autumn cabbage and the plants transplanted to the field about the same time, so that they will make their vegetative growth during the late summer and autumn. Where winters are mild, the plants can be left in the open, but in more rigorous climates at the approach of cold weather, a small number of plants can be lifted with earth adhering to the roots, stored in a suitable root-cellar, and the following spring transferred to the open to form heads.
L. C. Corbett.