Flurprimidol Is Effective at Controlling Height of `Star Gazer' Oriental Lily

Abstract

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·L–1 (ppm) did not control plant height and foliar sprays of flurprimidol concentrations ≥80 mg·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·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·L–1) were applied and a concentration of 25 mg·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·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.