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There are three types of heating that you can use, based upon which fuel is used to power them - Paraffin, Propane Gas or Electricity, and whether you have an electricity supply available in your greenhouse.

Electric Greenhouse Heaters - these greenhouse heaters range from simple Tubular Heaters to 3kW Fan Heaters. Tube Heaters are all low-wattage, meaning that they are very cheap to run, however this also means that the level of heat given out is fairly low. These don't come with any thermostatic control built in, but you can wire these into any of our thermostats if you need more control than simply using the on/off switch. Tube heaters do get hot to the touch, and we recommend that a safety guard is fitted. Tube heaters are recommended for frost-protection only in very small greenhouses, or to protect plants in a small area of the greenhouse. We stock Hylite tube heaters in lengths from 1ft to 5ft.

All other electric greenhouse heaters have a fan and thermostat. These functions provide greater air circulation, helping to prevent damping off and plant disease. The price range is quite wide, and the difference between these heaters is; 1. the quality and therefore accuracy of the thermostat ; 2. the volume of air that the fan can distribute per hour. The accuracy of the thermostat can vary considerably because the higher-priced heaters use a more accurate capillary thermostat to control the heat functions, and therefore the temperature range between switching on and off is relatively small. However, a cheaper heater will provide adequate heating, but because of the nature of the components inside, you will have more hot-spots and cold-spots inside your greenhouse, and the temperature differential between On & Off on the thermostat will be much closer on more expensive models. As with any appliance, you do get what you pay for, and should you have plants of great value then you should invest in an appropriate heater.

A fan heater near the bottom of the price range will typically have a plastic casing which is obviously more prone to damage than the more expensive models which have a tougher metal casing.

We stock electric greenhouse heaters from Parasene, Bio Green and HotBox.

Paraffin Greenhouse Heaters - there are a few different paraffin heaters available to heat your greenhouse. These all have a tank into which you pour paraffin. The fuel then soaks into the wick and you light this manually to create heat. The wicks need to be adjusted to the correct level to ensure an even burn with minimum smoke. Paraffin heaters don't have any thermostats or heat level controls. When considering this type of heater always think about where you will purchase your fuel, as paraffin is becoming harder to find locally. We stock paraffin heaters made by Parasene and BioGreen.

Gas Greenhouse Heaters all use LPG Propane fuel, available in red canisters in various sizes. The range of gas heaters starts from the simple Frost Buster, which has no thermostat and is designed to frost-protect small areas. All our other gas heaters have thermostats and electronic ignition, and range in capacity from 1.9kW to 6kW. These are connected to the gas canister by a propane hose and regulator, which regulates the pressure of gas into the heater.

To run a heater of this type, simply attach the regulator and hose between the canister and heater, push the igniter and set the dial to the required setting. The heater will then run itself, turning on and off as required to maintain the desired temperature.

In summary, an electric or gas greenhouse heater will provide much more controllability than a paraffin model. Electric models are the simplest, as there is no need to purchase any gas or paraffin. The more you spend the better quality components will be in your heater, and the longer the warranty will be.

What capacity of heater do I require?

We have drawn up the following table to help you determine the approximate capacity of heater that you require, depending on whether you want to provide good levels of heat, or just provide frost-protection.

Our advice is to use this as a guideline only, and buy the biggest capacity heater that your budget allows.