In this guide we’ll look at the best greenhouse heaters for the UK market.
I’ve compared performance, size, build quality and cost
to give you my top recommendations.
What Are The Best Greenhouse Heaters?
More Detailed Greenhouse Heaters Reviews
The Bio Green PAL 2.0/GB 2KW Palma Heater is the best electric greenhouse heater as it is powerful, economical and has a digital thermostat.
This electric greenhouse heater is compact and durable and features an IPX4 rating which means it is splash-proof. The build quality is excellent, with a mainly stainless steel construction, and the unit looks good, too. The heater features a handy carry handle so it is easy to move around. The heater also has a 190 cm cable, so it is easy to position in the right place.
This heater has a separate digital thermostat which can be set to temperatures from-50C to + 99C, making it easy to maintain the perfect temperatures for your plants. The 2KW motor is effective and powers a fan that provides an air circulation rate of 163 m3/h. This means it creates an even temperature throughout the greenhouse with no hot or cold spots. Good air circulation is also vital to prevent mould, mildew and fungal diseases. The heater is suitable for greenhouses and other spaces up to 39 sq. ft.
Overall, this is an effective and simple to use heater that you can just set up and leave to protect your plants over winter. As it is light and easy to carry this is also the best portable greenhouse heater as you can easily move it to other spaces as required.
This 2KW Electric Greenhouse Heater is robust, reliable and thermostatically controlled so will protect your greenhouse plants with no fuss.
This compact yet sturdy heater features a handy carry handle to make it easy to move around to wherever you need it. The heater has a 2KW motor and is thermostatically controlled so you can keep your greenhouse at just the right temperature for your plants. The heater also includes a 3-speed fan that runs continuously to increase air circulation. The fan provides air circulation at a rate of 186 m³/hr which keeps your plants healthy and prevents the growth of mould and mildew. This product offers great value for money for a heater with such a good build quality and range of features.
This reliable and sturdy greenhouse heater has a thermostatic control so you can set it and leave it to protect your plants making this the best small greenhouse heater in this price range.
The Biogreen WM-P4 Warmax Power4 Paraffin Heater offers a simple yet effective way to keep your greenhouse frost free without the need for mains power, making this the best paraffin greenhouse heater.
This heater is simple to use. You simply insert the wick, fill the canister with paraffin, light it and trim the wick. It is important to trim the wick quite low to prevent smoking. This tiny little heater will keep the average 8ft x 6ft greenhouse frost-free in the harshest weather conditions. The item has a nice traditional design, is reasonably cheap to buy and is cost-effective with 4 litres of paraffin being enough to keep it alight night and day for a week.
Overall, this is a simple product that keeps your greenhouse frost free and is ideal for use if you have no mains power in your garden building.
The Dimplex ECOT1FT Tubular Heater is compact, effective and thermostatically controlled making it the best small greenhouse heater.
This heater is easily mounted on brackets so you can have it out of the way and taking up no floor space. The mounting brackets and full instructions are included. It is IPX4 rated which means it is splash-proof and safe for use in the greenhouse. The heater has low wattage and so is safe and cheap to run, yet still provides a frost-free environment for your plants. The thermostatic control is easy to set and accurate so you can get just the temperature you need. The heater comes with a 1.5-metre cable and a 3 pin plug
This heater offers a safe, cost-effective and cheap to run option for keeping your greenhouse frost free in winter.
The Bright Spark Portable Gas Heater is convenient to use, cost-effective and offers instant heat for the greenhouse making this the best gas greenhouse heater.
This light and portable heater has a handy carry handle so can easily be moved wherever it is needed. Despite its lightness, the steel construction feels durable and long-lasting. The heater features a piezo automatic ignition for easy lighting. The heater provides instant heat and is fuelled by a butane canister. Each canister will give up to 3 hours on full heat. The product also has an easy to use temperature control.
This is a low-cost solution to heating a greenhouse during times of freezing weather and is handy if you have no mains power in your greenhouse.
Different greenhouse heaters will give out different amounts of heat. What you choose will depend on your needs. If you want to keep a standard greenhouse frost-free, then a high heat output will not be necessary. You may want to keep your greenhouse warmer than this, say 7 degrees Celsius to keep tender plants alive over winter. Again, this will not require a huge power output, but you may need more than a small paraffin heater will provide. If you want to keep tropical plants or warm a conservatory up enough to sit in through winter you may need a higher output, such as a 2-kilowatt heater. Many electric heaters have a variety of heating modes and a thermostat so you can set them according to your needs. Some gas heaters also offer a range of heat settings.
Most greenhouse heaters are designed to be as energy-efficient as possible. It is difficult to compare them as they use a range of fuels for power. However, to keep a greenhouse frost-free will add very little to your heating coats whether you use electric, gas or paraffin.
A thermostat is a very handy feature on a greenhouse heater as it ensures the area remains at the exact temperature you want all the time. In addition, a thermostat ensures you don’t waste energy heating your greenhouse to a higher temperature than you need.
What size heater do you need for a greenhouse?
This question is difficult to answer as it will depend on the size of your greenhouse, the material it is made from and any insulation you have fitted as well as what temperature you want the greenhouse to be maintained at.
However, as a rough guide, the table below will show the size spaces that can be kept frost-free or heated by power output.
1Kw – Heat 48sq ft – Frost Protection 80sq ft
2Kw – Heat 60sq ft – Frost Protection 120sq ft
3Kw – Heat 120sq ft – Frost Protection 260sq ft
4Kw – Heat 150sq ft – Frost Protection 350sq ft
6Kw – Heat 200sq ft – Frost Protection 500sq ft
What is the best type of greenhouse heater?
The best greenhouse heater is the one that meets your requirements perfectly. This will depend on the size of your greenhouse, your access to mains electricity and the specific conditions your plants require. If you have mains electricity, then an electric fan heater with a thermostat will be your best choice. This will ensure you can maintain your greenhouse at the right temperature over winter as well as increasing air circulation to prevent mould, mildew and fungal diseases.
A greenhouse heater can help you make the most of your greenhouse allowing you to keep tender plants over winter as well as starting off new seedlings earlier in the spring. I would recommend the Bio Green PAL 2.0/GB 2KW Palma Heater as it has a 2KW motor, a powerful fan and a separate digital thermostat.