How can the cold affect my yield?


Every day the temperature continues to drop. We are getting closer and closer to those very cold winter months. Many people will already be preparing their grow rooms for the drop in temperature. For warm season crops like tomatoes, peppers and cucumbers temperatures should be 18°C – 21°C at night and 21°C – 28°C, 30°C max in the day. For cold season crops like broccoli, lettuce and onions temperatures should be 10°C – 16°C at night and 16°C – 21°C in the day. Plants can sense temperature changes, if your plants drop below their minimum temperature they will think it is time to stop growing as they will think it is winter which is the time most plants will begin to die.

So what does actually happen when you accidentally let your grow room get too cold? Once your plants reach below the minimum temperature shown above they are universally at risk of death. Your plant's metabolism begins to slow down and the uptake of nutrients begins to decrease. This will ultimately stop the development of your plant.

How can I keep my plants at the optimum temperature?

If your grow room is cold you will need to invest in heating systems, to begin with, radiators and fan heaters will help with this as well as your lighting system. You want to make sure however that you do not overheat your room using a thermostat heater is best because too much heat can be just as bad.

With the cold comes the wet weather which can create a moist breeding ground for diseases and pests specifically those looking for the warmth. Using a dehumidifier can help prevent this, but remember that your plants do need humidity in order to maintain their health. We recommend aiming for 60%-70% for your humidity.

Another easy way of making sure that your room does not drop in temperature is by using a fan speed controller. Setting your day/night temperatures will decrease fan speeds when the temperature drops to allow your heating devices to warm the room back up to optimum temperature.

Another thing to watch out for is your water temperature if you are using a hydroponics system. If you are doing a new nutrient mix and replacing the old water make sure that it is at a suitable temperature. If the temperature is too low your plants will go into shock and this can have devastating effects on your crop. On the same hand if you put it in too hot you lose oxygen from the water which can directly affect the growth of your plant. To avoid this happening you should make sure that your water is between 18°C – 26°C. A tank heater can help to maintain the steady temperature of your water.

If you would like to find out more about the products which we recommend to keep your plants healthy this winter then please contact one of our sales team.

Sherridan Rhodes