Two field experiments were conducted at Mallawi Agricultural Re­search Station during 1995 and 1996 seasons to study the effect of sowing dates (sl and s2), thinning time, (T1 and T2) and time of nitro­gen application (N1, N2, N3 and N4 on yield and yield commponts)of seasme. A split-split plot design was used. It was concluded from results that a higher growth measurements of plant height, low stem height to the first capsule, higher fruiting zone, number of capsule per plant, seed weight per plant, 1000 seed weight, seed yield per feddan, and oil per­cent recorded from early sowing (mid April), thinned plants after 20 days from sowing, and applied on third of nitrogen at sowing, another third at thinning and the last third at the beginning of flowering. The in­teraction between sowing dates and thinning time had significant effect on plant height, fruiting zone length, and seed yield per feddan in both seasons in addition to first capsule height and seed yield per plant in the first and second season respectively. The highest values were obtained by sowing in mid April with thinned plants after 20 days from sowing. The interaction between sowing dates and nitrogen application was sig­nificant for the first capsule height and seed yield per feddan in both seasons in addition to 1000 seed weight and seed yield per plant in the first and second seasons respectively. While the interaction between thinning time and time of nitrogen application had significant effect on the first capsule height and seed yield per plant in the first and second seasons respectively. Seed yield per feddan strongly correlated with dif­ferent yield components attributes to different correlation coefficient levels.