Ancymidol, chlormequat, and daminozide were evaluated as growth retardants on forced dahlias. Only ancymidol was effective in reducing plant height, and at 0.25 to 2.0 mg per plant it did not affect the date of flowering, flower size, or the number of shoots produced from the tuberous roots. Treatment by soil drench was more effective than a foliar spray. The most consistent effects were obtained when ancymidol was applied 2 weeks after planting. Dahlia cultivars differed in the degree of response to ancymidol. Optimum rates must be determined for the cultivars which are suitable for pot plant forcing for spring marketing.