Red pepper grows well in high temperature. Proper temperature to grow is 25~28 °C during the day and 18~22 °C during the night. It's better not to drop the temperature under 13 °C. When temperature stabilizes in 20~25 °C it is the best time for plants to bear fruits. If the temperature drops under 15 °C or rise over 30 °C, fertility of the plant is seriously damaged resulting in windfall and malformed fruit.