These classes are considered cool season vegetables and are best grown during periods of the year where daytime temperatures range from 65-85 degrees. These temperatures make the growing of brassica highly successful as a spring and late summer/fall crop. Brassica grows well in soils that are well drained, but retain some moisture and soils high in organic matter are the best. Soil pH should be in the range of 6.0-7.0 for optimum growth. These are full sun vegetables, but can tolerate 2-3 hours of indirect sun, especially late in the day.
Source: The Cook’s Garden