Flurprimidol is effective at controlling height of 'Star Gazer' oriental lily

Flurprimidol preplant soaks, foliar sprays, and substrate drenches were compared to commercially recommended concentrations of uniconazole as a preplant bulb soak and a foliar spray for height control of 'Star Gazer' oriental lily (Lilium hybrids). Foliar sprays of uniconazole at 10 mg center dot L-1 (ppm) did not control plant height and foliar sprays of flurprimidol concentrations 80 mg center dot L-1 provided only minimal height control. Substrate drenches of flurprimidol at 0.5 mg/pot a.i. (28,350 mg = 1 oz) controlled plant height, resulting in plants 45.3 cm (17.83 inches) tall, which were 24% shorter than the untreated control. Uniconazole preplant bulb soaks of 5 and 10 mg center dot L-1 controlled plant height, resulting in plants 41.8 cm (16.46 inches) and 37.8 cm (14.88 inches), respectively. Preplant bulb soaks of flurprimidol (25 to 400 mg center dot L-1) were applied and a concentration of 25 mg center dot L-1 resulted in plants 47.7 cm (18.78 inches) tall, which were 23% shorter than the untreated control. Flurprimidol substrate drenches and preplant bulb soaks at concentrations of 0.5 mg/pot a.i. and 25 mg center dot L-1, respectively, were effective in controlling height in 'Star Gazer' lily. In Expt. 2, flurprimidol substrate drenches were applied as either a single or two split applications. A one-time flurprimidol substrate drench of 0.5 mg/pot a.i. provided similar control as two split applications of 0.25 mg/pot a.i.