Effect of sowing time and plant density on the growth and production of roselle (Hibiscus sabdariffa)

Abstract

Experiments were conducted to see the response of roselle to different sowing dates and plant spacing. Six different sowing dates (seed sown at 10 days intervals on 6th May, 16th May, 26th May, 5th June, 15th June and 25th June) were used as main plots and six different planting densities (2, 3, 5, 7, 11 and 18 plants m-2) as sub plots. Results showed that plant height, stem diameter, number of leaves, number of calyces per plant, fresh weight of calyces per plant, dry weight of calyces per plant and calyces yield per ha was significantly affected by different sowing dates as well as planting densities. Maximum plant height (175 cm), stem diameter (3.1 cm), number of leaves per plant (636), number of calyces per plant (104), calyces fresh (206 g) and dry (21.7 g) weight plant-1, and calyces yield per ha (1427 kg) was recorded for the plants sown on 6th May, while these traits decreased with delayed sowing. For plant densities, the tallest plants (155 cm) with maximum calyces yield per ha (2496 kg) were observed at the highest density of 18 plants m-2, though the per plant stem diameter (2.9 cm), number of leaves (653), number of calyces (99), calyces fresh (205 g) and dry (24.9 g) weight were higher at the lowest density of 2 plants m-2. It was concluded that 6th May sowing and 18 plants m-2 planting density produced the highest yield per ha in roselle crop.