Dutch researchers have found that the best average temperature to grow tomatoes in a greenhouse is around 24°C. This temperature can (and should) fluctuate throughout the day.
The development of tomatoes responds to the 24h mean temperature. Meaning that the environmental temperature in the tomato greenhouse can be slightly higher during the day, when the temperature in the evening is below 24°C. A 26/22°C day and night temperature gives an average temperature of 24°C.
Please note that temperature integration is only possible within the temperature range in which the relevant relationship varies linearly with temperature.

