Humidity in a cultivation room is perhaps the most underrated growth factor. We use relative humidity RL as a unit to measure this and to make adjustments.
A dry air will accelerate the evaporation of the moisture from the leaf and a very moist air will delay this. A plant must always evaporate some water so that there is room in the plant for new water from the medium in which new nutrients are dissolved.
The plant is like a pump that works on solar energy. However, if the relative humidity around the plant is too low, the plant will evaporate more than it can absorb and the plant will experience a growth disorder and may eventually dry out.
If the humidity around the plant is extremely high, the plant will eventually grow little.
A balance in this is therefore very important.The humidity temperature is also important. There are systems that can easily blow cold water into the air. However, this cold moisture will naturally also slow down growth. It is best to use lukewarm water.
Hobby growers who do not have a humidifier at their disposal can best spray the leaves regularly during the first 4 weeks.