by Nebula Haze
Many cannabis growers struggle with heat in their grow room. What’s the best grow light for a hot grow space? There is a clear answer…
LED grow lights perform better in heat
Cannabis plants under LEDs thrive in warm temperatures
Cannabis plants grown under LEDs can thrive under higher temperatures than the same plants grown under a big bulb light like an HPS or LEC.
I’ve found cannabis plants under LEDs seem to perform best when the air temperature is about 80°F / 27°C or a little warmer when the lights are on. However, they will still grow at higher temperatures as long as you take good care of them.
LED-grown plants can also handle warm nights, so if you’re really struggling with heat you can switch your grow light to turn on at night and have the plant’s “night” (dark period) during the hottest part of the day to reduce their exposure to heat.
LEDs Ideal Air Temperature: 80-85°F / 27-30°C
However, LEDs are bad for the cold…
LED grow lights are not suitable for growing cannabis in the cold because LEDs do not put off much heat or produce enough infrared light to keep plants warm from the inside. In general, plants grow slower and produce smaller buds in cooler temperatures because photosynthesis needs heat. Unlike HIDs which put off significant infrared light, LEDs don’t change the temperature of leaves, so the leaves are essentially always the same temperature as the air. That means with LEDs you want to keep a nice warm environment for the fastest growth and biggest buds.
If it gets too cold, cannabis plants under LEDs grow slow and buds don’t thicken up properly.
All cannabis plants grow poorly without warmth, but LED-grown plants are particularly weak to the cold.
