Capsicum Seeds F-1 Hybrid YellowOverview Sweet pepper is more sensitive to unfavourable environment. The optimum night temperature for quality fruit production is 16 18C. When the temperature falls below 16C for extended periods, growth and yields usually decrease. It can tolerate day temperature over 30C and night temperature 21 24C The color of bell peppers changes from green to yellow, orange, and red the longer it is allowed to mature on the plant Orange and yellow bell peppers