Sun, wind and heat on a terrace
Grow more on your terrace.
Terraces do not have the same microclimate as the ground below them. South-facing walls and light-coloured paving reflect heat back onto plants throughout the day, creating a heat island that can be 8 to 15 degrees warmer than surrounding air. This is an advantage in cool climates for heat-loving crops like peppers and basil, and a serious stress factor in already-warm cities during summer heat waves.
Wind is the other defining factor. Even a gentle breeze is felt more strongly at height, and gusts that would barely move a garden tree can desiccate container soil within hours. Taller terraces and corner positions face the worst exposure. Map your wind direction before placing containers: use fixed structures and dense screening plants to create wind shadow for vulnerable crops.
Shade cloth at 30 to 50 percent density can cut heat stress on the hottest exposures without blocking enough light to harm fruiting crops. Light-coloured containers also absorb less heat than dark ones, keeping root zones cooler on south-facing terraces in summer.