StormChaos
New Member
2) Humidity has often been 30s% to 40s%, but has dipped down to 26% and been as high as 77% (short lived). I put a humidifier in the room last night and will see if it brings it up at all - would like it at least above 40%.
Seedlings and Vegatative plants grow best when the RH is 60 to 70% Flowering plants grow best in 40 to 60%
Lower humidty discourages disease and pests. As with tempature, consistent humidity promotes healthy and even growth. RH affects the transpiration rate of the stomata. WHenhumidty is high water evaporates slowly. The stomata close, transpiration slows... plant growth slows.
Transpiration in dryier conditions will be rapid ONLY if there is enough water for the plants roots to draw in. If the water supply is insuffienct - the stomata will close to protect the plant from dehydration... and again growth will slow.
When the RH is above 70% the pressure is toomuch outside the leaf and the too little inside -stomata close...plant growth slow.
Humidity over 80% discourages spider mites and encourages fungus and root/stem rot. Humidty 60% and less reduces chances of fungus and rot.
40 to 60% is a safe level that encourages transpiration and discourages fungus growth.