Sumagic Plant Growth Regulator Gets a Label for Some Vegetable Transplants

Gordon Johnson, Extension Ag Agent, Kent Co.;

Sumagic (active ingredient uniconazole) is a plant growth regulator from Valent Professional Products used in greenhouse production for plant height control. It has received a label for certain fruiting vegetable transplants. This is the first plant growth regulator that has been labeled for vegetable transplants since food crops were pulled from the B-Nine label in 1989. Since then, transplant growers have had to rely solely on temperature, water, or fertility regulation to maintain compact plants and prevent leggy growth.

Sumagic is now registered for use as a foliar spray on tomato, pepper, eggplant, groundcherry, pepino and tomatillo transplants in the greenhouse (no other crops are registered at this time). The recommended label rate is 0.52 to 2.6 fluid oz per gallon (2 to 10 ppm) and one gallon should be sprayed so it covers 200 sq ft of transplant trays (2 quarts per 100 sq ft). The first application can be made when transplants have 2-4 true leaves. One additional application may be made at the low rate, 0.52 fluid oz per gallon (2 ppm), 7-14 days later, but you cannot exceed 2.6 fluid oz of total product (per 100 sq ft) for a season. Growers are advised to do small-scale trials on a portion of their transplants under their growing conditions before full scale adoption. Sumagic is registered for use on labeled vegetable transplants in all states except California and New York. However, the supplemental label must be in the possession of the user at the time of application. Go to for this supplemental label.