Ornamental cabbage and kale are excellent plants for fall color. Plants require medium levels of fertilization, growing optimally with 150 to 200 ppm N. The target substrate pH values are between 5.8 and 6.2. The most common nutritional disorder of ornamental cabbage and kale is providing insufficient fertility, which results in lower leaf chlorosis (yellowing) and drop. In addition, like all members of the cabbage family, they are unforgiving if drought stressed and if wilted may exhibit stalled growth.
Read more at e-GRO (Brian E. Whipker, Josh Henry, W. Garrett Owen)