Growth and flowering of chrysanthemum cultivars as affected by Alar and levels of slow-release fertilizer

The effects of Alar and slow-release fertilizer (Osmocote) on growth and flowering in four chrysanthemum cultivars (Kodiak ‘yellow’, Ivyridgf ‘white’, Auburn ‘red’, and Lansing ‘pink’) grown under greenhouse conditions were evaluated. Four concentrations (0.0 “control”, 1500, 3000, and 4500 ppm) of Alar and four levels (0.0 “control”, 70, 140, and 280 mg kg -1 soil) of Osmocote were used. Among the different treatments of Alar, the 1500 ppm significantly increased the number of branches, number of leaves, leaf area, relative chlorophyll content, inflorescences diameter, the number of inflorescences and concentrations of N, P and total K. The remarkable increase in growth (e.g. plant height and dry weight) and flowering parameters (e.g. number of flowers, flower diameter and flower dry weight) were found with Osmocote treatment at 70 mg kg -1 soil compared to other treatments. Generally, we proved that all cultivars treated with 1500 ppm Alar were compact and had large flower diameters and the best vegetative growth and flower quality with application of the slow-release fertilizer Osmocote at 70 mg Kg -1