Two field experiments were carried out in order to evaluate the effects of planting date, method and date of weed control on yield and yield components of cumin in the experimental research field, Faculty of Agriculture, during 2006 and 2007. Treatments included planting date (30 December, 20 January and 30 February), weeding date (first true leaf, start of branching and beginning of flowering stages) and weed control methods (hand weeding, fire treatment and control). The results showed that there were significant differences in the number of weeds between different sowing dates, weeding dates and control methods. The highest mean density and biomass of weeds were obtained on the planting date, 30 February, and when weed was controlled at the first leaf appearance stage with fire treatment. Fire treatment reduced weed growth in the first half of growing season, however, hand weeding significantly reduced weed density and biomass in the second half of cumin growing season. The first planting date caused the lowest mean weed biomass and the highest cumin yield compared to later planting dates. Hand weeding treatment contained lower mean weed density and biomass compared to fire treatment, however, cumin yield was lower in hand weeding plots than fire treatment. The highest cumin yield was in 30 December and the lowest was in 30 February. However, delaying of sowing date decreased the straw yield, number of umbelets in umbel, number of seed and biological yield. The highest yield of seed, straw and biologic was obtained in hand weeding methods.

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