Published online by Cambridge University Press: 27 March 2009
Field experiments were conducted during 1983–85 and 1984–86 on an entisol at Lucknow, India. Dry herbage, essential-oil yields and nutrient uptake increased significantly with the application of 83 kg K/ha. Considering the means from both experiments over a two-year cropping cycle, the application of 41·5 kg K/ha in four splits exceeded the zero K control by 6·8 t/ha (dry matter) and 233 kg/ha (oil), and exceeded a basal application of 83 kg/ha K by 2·8 t/ha (dry matter) and 109 kg/ha (oil). Amounts and methods of K application showed no effect on oil quality. Application of 41·5 kg K/ha in four splits, one after each harvest, is recommended to obtain maximum yields in this perennial grass.