Effects of Plant Spacing and Harvesting Age on Growth and Yield of Sage (Salvia officinalis L

Abstract

The experiment was conducted at Wondo Genet Agricultural Research Center, Southern Ethiopia from 2015 to 2017 cropping seasons to determine the optimum harvesting age and plant spacing of sage to maximize essential oil yield. The experimental design was RCBD in factorial arrangement with three replications. The treatments were four harvesting ages (3, 4, 5 and 6) months after planting and three plant spacing (30 cm × 30 cm, 60 × 60 cm and 90 × 90 cm). The study showed that spacing had a highly significant (p≤0.001) influence on fresh leaf weight per plant, dry leaf weight per plant and essential oil yield per hectare; highly significantly (p≤0.01) influenced plant height and dry herbage yield per hectare, significantly (p≤0.05) influenced fresh herbage yield and non-significantly influenced essential oil content. On the other hand, harvesting age highly significantly (p≤0.001) influenced plant height, fresh leaf weight per plant, dry herbage yield per hectare, essential oil content and essential oil yield; and also, significantly (p≤0.05) influenced dry leaf weight per plant. The highest essential oil yield (98.16 and 106.73 kg/ha) were obtained from 30 × 30 cm spacing and five months after planting respectively.