Grow Room Heating and Heaters

Maintaining a minimum temperature in your grow room is essential for year-round growing success in the UK climate. During winter months, temperatures in unheated grow tents, lofts and outbuildings can drop well below the minimum threshold for healthy plant growth — causing chilling stress, nutrient uptake failure and root dysfunction that severely impacts yield and plant health. A properly selected and controlled grow room heater maintains the minimum temperature your plants need to thrive regardless of outdoor conditions.
Temperature Requirements for Indoor Plants
Most indoor crops have an absolute minimum temperature of 15°C for root function and active nutrient uptake. Below this threshold, root enzyme activity and active ion transport slow dramatically, even if the nutrient solution is present and correctly balanced. The optimal growing temperature during lights-on is 22–28°C depending on CO2 level and growth stage. During lights-off, allow temperature to drop no lower than 16–18°C — a drop of 5–8°C from lights-on temperature is natural and beneficial for many plants, but larger swings cause stress and slow growth.
Thermostatically Controlled Fan Heaters
Thermostatically controlled fan heaters are the most practical heating solution for grow tents and small grow rooms. Set the thermostat to your minimum target temperature and the heater activates automatically only when needed, maintaining the set-point without wasting energy. Position the heater so that warm air circulates freely — place it low in the tent with the outlet facing upward, working with natural convection to distribute heat evenly.
For larger rooms and outbuildings, tube heaters provide an energy-efficient low-level background heat that prevents frost and maintains a minimum temperature without the higher cost of running a fan heater continuously. We have been helping UK growers maintain year-round growing environments since 2017. Browse our full heater range below.