Height Control of Lilium longiflorum Thunb. ‘Ace’ Using Ancymidol Bulb-dips1

Abstract Ancymidol [α-cyclopropyl-α-(ρ-methoxyphenyl)-5-pyrimidinemethanol] applied at concentrations above 25 ppm active ingredient (a.i.) as a quick bulb-dip prior to cooling significantly reduced ‘Ace’ Easter lily height. Postcooling dips were not as effective and postemergence soil drenches were least effective. There was a trend toward delayed emergence and delayed flowering with increasing ancymidol concentrations when applied as bulb-dips either prior to or after cooling, however, significant delays occurred only with higher concentrations applied after cooling.