the effect of seasons (winter and summer) and drying on the yield and composition of essential oil obtained from the leaves of ocimum kilimandscharicum, cultivated at the subtropical conditions of north india, was examined by combined gc and gc/ms analysis. this chemotype was found to be rich in camphor (winter 48.9%, summer 58.9%), 1,8-cineole (winter 22.2%, summer 14.8%), and limonene (winter 5.5%, summer 5.6%). the yield of oil was observed to be more in summer (0.8%) than in winter (0.6%). on shade drying of the leaves, no effect was observed in the yield of oil in winter season. however, in summer, yield was slightly reduced on drying (from 0.8% to 0.6%). camphor, the major constituent of the oil, showed slight degradation in quantity during drying in both winter and summer seasons.