Abstract: Vegetation comprising herbaceous and woody ornamental plants and vegetable crops are treated by applying to the vegetation a nitrogen containing fertilizer and from 0.006 to 6.0 pounds per acre of a plant growth regulator. The plant growth regulator is one which regulates the growth of the vegetation by retardation of gibberellin synthesis. The ratio by weight of nitrogen in the fertilizer to the plant growth regulator is at least forty to one.

Abstract: Nitrogen containing fertilizers are combined with a plant growth regulator, of the type which retards gibberellin synthesis in plants, in a ratio of nitrogen to plant growth regulator of at least 40 to one. The resulting combination fertilizer composition, when applied to vegetation at the rate of 0.006 to 0.6 pounds per acre of plant growth regulator, delivers nutrients to plants in a fashion that more closely approximates their needs than any previously known plant nutrient compositions. Preferred plant growth regulators which operate by retarding gibberellin synthesis are paclobutrazol and flurprimidol which may be used as the only plant growth regulator in the combination fertilizer composition or together with a very small amount of a second plant growth regulator, such as mefluidide.