Temperatures are dropping in many parts of the world and unfortunately, cannabis plants don’t like the cold. In fact, most cannabis strains grow significantly slower once the temperature gets under 60°F (15°C), and freezing temperatures can cause major injury or even plant death.
Be prepared for a power outage
This cannabis plant is happy to be inside out of the cold weather
In many areas, winter is actually the driest time of the year, as well as being the coldest. If you are not facing issues of relative humidity, then cold dry air will present problems of its own in the grow room. If air is taken in from outside at a temperature of 10°C and an RH of 50%, it will contain water vapour at 4.7g/m³. If this air is heated to 25°C without the addition of extra moisture, its RH will drop to around 20%, which is far too low for healthy cannabis plants to grow.
Controlling humidity of cannabis grown in winter
Let’s look at autoflowering strains as an example. In as little as 8 weeks from germination of the seed, you can have a ready-to-harvest cannabis plant. This means that a grower can avoid growing throughout the harshest part of the winter and maximize their growing opportunity.
I hope this clears it up for you