Plant growth regulator and method for using same

A composition for regulating the growth of plants in which an effective amount of chlorocholine chloride, poly[oxyethylene(dimethyliminio)ethylene(dimethyliminio)ethylene]dichloride, and choline chloride, is diluted in an inert carrier. The inert carrier may be water, a solvent, or a surfactant. The composition with the diluent forms a liquid solution, which is sprayed on the foliage of subject plants prior to harvest. At least one inorganic salt may be added to the composition to enhance the efficacy of the liquid solution. A first formulation of the solution, preferably including the inorganic salt additive, may be applied early in the plant's development to discourage rank growth without inducing Cut-Out. A second formulation of the solution, having no inorganic salt but including a greater amount of chlorocholine chloride, may be applied late in the plant's development, to induce Cut-Out.