Greenhouse - Stretch Control in Ornamental Cabbage and Kale

Along with mum and fall pansies, greenhouse growers have added ornamental cabbage and kale for fall sales. Controlling stretch in these crops can be difficult due to high temperatures during late summer. The following is information on height control using growth regulators in ornamental cabbage and kale.

Chemical growth regulators are required to control plant height of ornamental cabbage and kale. Sumagic foliar sprays between 8 and 16 ppm were effective in controlling height at a cost of $0.02 and $0.04, respectively. B-Nine at 2500 ppm also provided comparable control in limiting unnecessary stretch, with a cost of $0.01 per pot when sprayed twice. A B-Nine rate of 5000 ppm is also recommended at a cost of $0.01 per pot. Although effective in controlling height, it is not economically feasible to apply Bonzi or Sumagic as drenches, because the costs are 3 to 6 times that of Sumagic foliar sprays or B-Nine foliar sprays.

Information from "Ornamental Cabbage and Kale Growth Control with B-Nine, Bonzi and Sumagic Foliar Sprays" vby James L. Gibson and Brian E. Whipker in the Floriculture Research Series No. 142 from North Carolina State University.