nebulius said:

Stuff I read from various grow books.

Ideal temp is 72-76°F with variations from 5-10°F ok, larger variations in temp. increases chances of having issues. Plants produce maximum growth when exposed to a day temperature that is about 5 to 10°F higher than the night temperature. This allows the plant to photosynthesize (build up) and respire (break down) during an optimum daytime temperature, and to curtail the rate of respiration during a cooler night.

Temps above 85°F slows plant growth. Cannabis regulates it's oxygen uptake in relation to the ambient air temperature. High temperatures cause increased respiration, sometimes above the rate of photosynthesis. This means that the products of photosynthesis are being used more rapidly than they are being produced. For growth to occur, photosynthesis must be greater than respiration.

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lex0415 said:

I honestly believe this, some people say if it goes above 85F it doesn't matter but one time I had a plant and the first couple weeks it was just around 85F and it was growing less than an inch a day. After I dropped the temps to the mid 70F growth shot up between 1 and sometimes 2 inches a day. So temps being in the 70's is very important IMO. great post nebulius

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