The effects of different root zone volumes (2000, 4000 and 6000 cm?) on growth, water relations, stomatal responses, photosynthetic rate, mineral nutrition and yield of tomatoes (Lycopersicon esculentum Mill.) grown in sand culture were investigated . The plants were sampled for growth analysis fortnightly for a 56-day period. Leaf growth, stem and root dry weights were significanlty reduced with root zone volumes o f2000 and 4000 cm?. Total fruit fresh weight was reduced when plants were grown with decreasing root zone volumes. Root zone volumes, however, did not produce a significant effect on percentage of fruit dry matter and total soluble solids. The reduction in plant growth and development was associated with reduction in water potential, photosynthetic rate and mineral nutrient uptake when plants were grown in root zone volumes of 4000 cm? or less.