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Grow Room Temperature Control – What Happens if it is too Cold?

Much like humans, cannabis plants need certain temperatures to thrive during their growth. In an indoor set-up, you need to pay particular attention to the general temperature of the grow room. Serious issues can arise if your cannabis feels too hot or too cold.

Here, we go through the problems that can occur if your grow room is too cold. If you are seeing your plants behave in the ways explained below, it may be time to turn that thermostat up.

Cold Grow Room?

Firstly, we will explain what can happen to your plants if your grow room is too cold. We will then discuss how you can counteract these issues.

A cold grow room will likely slow down the growth of your plant. As a general rule, temperatures lower than 55-60F (10-15C) will slow down and eventual kill your plants. Indoor plants are far more susceptible to cold temperatures than hardier outdoor plants.

Cold temperatures in your grow room cab often lead to damp areas. In turn, this brings unwanted mould, which can have a significantly damaging effect on your plants. These low temperatures can also lead to over-purpling of the leaves.

Realistically, a temperature too hot or too cold for your plants can cause of plethora of issues including a change in the taste, smell, colour and density of your grow.

The Ideal Temperature for your Grow Room

During the vegetative stage of your plants growth, temperatures will need to be a little warmer than in the flowering stage. This is a key part of the cultivation process for your plants, so they need that little bit of extra heat to ensure success. A temperature of around 70-85F (20-30c) will suffice.

When it is time for the flowering stage, you can slightly reduce the temperature of your grow room to 70-80F (20-26c). Always remember that there should be around a 10 degree difference between night and day temps if you want to achieve the best results.

Essentially, it is all about reacting to a temperature that you believe doesn’t feel right. If you feel too cold in your grow room, your plants will likely feel too cold as well.

Cultivation information, and media is given for those of our clients who live in countries where cannabis cultivation is decriminalised or legal, or to those that operate within a licensed model. We encourage all readers to be aware of their local laws and to ensure they do not break them.


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