In this study, quantitative relationships were established between the combined effects of temperature (between 7.4 and 24.2°C) and light intensity (between 1.9 and 8.1MJm −2 d −1 ) on the number of leaves formed before the first fruit in tomato and aubergine. The number of leaves formed before the set of the first fruit (aubergine) or fruit cluster (tomato) decreased for both tomato and aubergine when daily mean light integral increased but effect of light decreased as temperature declined. Leaf number subtending the first fruit or fruit cluster in both tomato and aubergine declined linearly with decreasing temperature, particularly at the lowest daily mean light integral (1.9MJm −2 d −1 ). However, temperature had little effect on the number of leaves formed before the first fruit cluster of tomato and the first fruit of aubergine at the higher daily mean light integrals. At low temperatures, the effect of light was different for tomato and aubergine. The study showed that the appearance position of the first fruiting flower cluster and flower for tomato and aubergine, respectively could be controlled by controlling light and temperature in greenhouses.