I am growing some tomatoes in pots in a toy greenhouse. I've put a thermometer/ humidity meter inside.
The relative humidity changes from around 55% to 75%, and correspond to highest temperature of 26 Celsius (79 °F) and lowest around 17 °C (63 °F).
Both temperature and relative humidity are completely normal, but do plants prefer these changes? By which I mean, do the tomato greenhouse pros try to maintain a constant temperature and relative humidity, in order to maximize crop?