Efficacy of chemical retardants on growth and flowering in potted zonal pelargonium

Abstract

A pot experiment was conducted under glasshouse conditions with completely randomized block design where growth and flowering responses of two cultivars of Pelargonium × hortorum were studied using spray treatments of chlormequat or chlorocholine chloride or cycocel (CCC @ 500, 1000, 1500 ppm) and ethephon (350, 600, 1000 ppm). CCC at 1000–1500 ppm was found most effective in producing desirable and presentable potted pelargoniums where 15% dwarfing effect on plant height reduction was obtained along with an early flowering of 10–12 days as compared to control. Ethephon at 600–1000 ppm resulted in maximum height retardation (18.31%) in plants with more number of side shoots and 50% more plant spread as compared to the control. All ethephon treated plants resulted in delayed flowering. Both growth retardants have beneficial implications in large scale commercial production of potted zonal pelargoniums where axillary branching can be achieved with ethephon followed by cycocel foliar sprays to retard plant height and advance flowering.