Growth Retardants as an Aid to Adapting Freesia to Pot Culture

Abstract Freesia ( Freesia hybrida Bailey) corms were treated with paclobutrazol or ancymidol as a 5 mg a.i. soil drench, or with paclobutrazol as a 250 ppm preplant corm soak treatment. Both growth retardants significantly reduced plant height and inflorescence length, but had no effect on number of flowering spikes per pot or number of days to flowering. The preplant corm soak treatment was even more effective for height control than the soil drench application. Both compounds can be used to reduce plant height, allowing the adaptation of freesia to pot plant culture. Chemical names used : β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1 H- 1,2,4 triazole-1-ethanol (paclobutrazol) and α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidi nemethanol (ancymidol).