Climate Bananas need warm subtropical climate, adequate moisture and protection from wind. Although banana is grown in a large variety of climates, optimal climatic conditions for banana Most varieties of Bananas grow best with 12 hours of bright light and high humidity of 50% or higher. The ideal temperature range is around 26-30°C (78-86F) with RH regime of 75-85%. Growth begins at 18ºC, reaches optimal growth at 27ºC and stop entirely when temperature reaches 38ºC. Although Bananas grow best in bright sunlight, high temperature will scorch leaves and fruit. humidity and winds notstrongerthan 4 m/sec.