Grow Tent Too Hot? 8 Fixes Ranked by Cost
Above 85°F, growth slows and terpenes volatilize. Work down this list from free to expensive — most people solve it in the first three steps.
Free fixes
Run lights at night and dark during the hottest part of the day. Dim your LED by 10-20% — you will lose less yield than you think. Open a lower tent flap to increase passive intake.
Cheap fixes
Raise the light a few inches. Add or upgrade a speed controller so the exhaust fan runs faster. Shorten and straighten ducting — every bend and every foot of flex duct costs airflow.
Real money
A larger inline fan, ducting the exhaust out a window instead of into the same room, or a portable air conditioner conditioning the room the tent draws from.
The mistake to avoid
Do not blow cold air directly at the canopy from an AC unit. Condition the room, let the tent pull from it, and keep leaf-level airflow gentle.
Frequently asked questions
- What temperature is actually dangerous?
- Sustained canopy temps above 88-90°F cause real stress, foxtailing in flower, and terpene loss.