What to Consider When Buying Greenhouse Heaters

Last Updated on April 5, 2024 by Real Men Sow

Having a greenhouse is great for growing vegetables and fruits organically, plus, it is a great activity to do gardening! Winters and autumns are quite cold though and keeping warmth and humidity in your greenhouse can bring another set of challenges. Greenhouse heaters are great ways to get rid of this problem! However, you might want to consider some key factors before choosing the right machine for your greenhouse.

If you are new to greenhouse gardening, make sure you also read our beginner greenhouse gardening tips.

What to Consider When Buying Greenhouse Heaters

Greenhouse Size 

You will need more power to maintain a steady temperature in the larger spaces. You should also consider whether the greenhouse is insulated.

Two heaters may be required if you have one of the most impressive greenhouse designs on the market. Pin bubble wrap to the roof or walls to cut down on power consumption and lower your bill. This will add insulation to the greenhouse and reduce the heating power required.

Source of Power


The electric option is the most common option on the market. The thermostat is the best option if you are looking for benefits because it allows you to regulate the temperature in the room and also saves energy. Once the desired temperature is reached, no electricity will be used again until it is needed again.

These models must have some water protection in order to be successful. You should look for IPX4 and IPX6 when searching the market. These are the strongest ratings you will find. Units with these ratings, regardless of how moist the air is, will still function as usual.

You’ll find many different types of heaters: convection heaters, ceramic heaters, infrared heaters and radiant heaters are all possible. They all use the same technology but have different foundations. A fan will help distribute heat better, so it’s worth looking for one that has one. The fan will not only reduce moisture, but also prevent mold and other similar problems.

Some units can be used freestanding, while others can be mounted. It’s up to you to choose the model that suits your needs. It’s recommended to go electric because it’s easy to use, generates good power, and can be very efficient.


Paraffin is easy to maintain and can stimulate plant growth. If you are able to find paraffin at a reasonable price (which can be difficult), then you won’t have any problems paying your electricity bill. The unit will continue working when there is no power.

The heater must be manually adjusted, so it can burn until there is no fuel. There is a possibility of mould growth from the water that’s produced. Paraffin, however, can protect the greenhouse from frost, and is stronger in temperature regulation.


You’ll find propane gas models as the third and final source of power for greenhouse heaters. The best thing about a propane-powered heater is that it is cheaper than paraffin. Also, the propane gas bottles can be easily found across the country.

Propane gas is the most harmful of all three options in terms of moisture. Even if you only leave the greenhouse for a few days, it can cause serious damage to your plants and the integrity of your greenhouse. You should make sure you have the motivation and time to inspect and replace the bottles every once in a while you maintain the greenhouse. This fuel is used by many patio heaters.

It is becoming increasingly difficult to find heaters with thermostats, despite the lower price of propane.

Power Rating 

Each heater will have a power rating. It’s usually listed in kW (kilowatts). Most heaters will offer between 1kW to 3kW. This is a significant difference for greenhouses. A small greenhouse will not require a powerful heater, but it is worth considering a more powerful model if you plan to grow your greenhouse.

It’s best to measure the greenhouse first, and then compare it to the airflow promises on different models. You can feel confident that the greenhouse will work in the space you have available if the coverage is adequate. Insulation is important because insulated greenhouses don’t require powerful heaters.

Most people have what the industry calls ‘small’ greenhouses. 2kW heaters are efficient and allow for more work.


It may sound obvious, but it is important to establish a budget before you begin looking at more expensive models. A heater’s price range can vary depending on what you need.

Best Greenhouse Heaters


  • Huge 3kW of power
  • Adjustable thermostat
  • Cold-rolled steel body
  • Emits no humidity, fumes, or odors
  • Passes all waterproofing requirements

Modern Life has the answer to your question about power, which is why it’s the most important feature of your greenhouse heater. According to Modern Life, it takes five minutes for the heaters to warm a 20-square-metre room. The heater can heat up to 60 square meters, according to the manufacturer.

The difference between this model and other models is the number of features that you get. We should start with the 3kW power, as this is something that you won’t find in many other models. You can adjust the power to suit your space by selecting from 30W, 1500W or 3000W. The unit also has overheat safety shut-off, the adjustable thermostat, the stainless-steel heating elements, noiseless fan and fixed safety bracket.

It feels like a greenhouse heater, all things considered. The heater’s life expectancy will be extended by using a dust-proof motor. Meanwhile, the fan that is quieter than the rest of the unit prevents us from getting frustrated.


  • Heating output of 2000W
  • Stands on the floor and offers IPX4 splash-proofing
  • Offers digital thermostat

Although this greenhouse heater is powerful, it won’t immediately mean it would be efficient in your greenhouse. The heater is durable due to its stainless-steel design. Bio Green designed and manufactured the heater. It can be used in any room measuring 39 square feet. This includes greenhouses and storage rooms as well as basements and outbuildings.

This is a great option if you are looking for efficiency without spending a lot of money on energy. The heat will circulate quickly once it is turned on. This means that there won’t be cold spots in corners. The thermostat can be set to the desired temperature, which could be very important depending on the contents of the greenhouse. The digital version is slightly more expensive but provides an impressive accuracy of +/- 2 degrees.

It’s easy to use and will last many years. Bio Green also has a trusted manufacturer that will assist you if you have any issues with your unit.


  • Up to 135w available in power
  • Uses similar energy levels to a lightbulb
  • Provides consistency for your greenhouse
  • Has a variety of other uses

The LightHouse Eco Heater is the most affordable. This heater can create a stable environment that will support plants no matter what the weather outside is like. Even on the coldest winter days, temperatures can stay stable so that your plants and vegetables can grow naturally.

The power output is lower than what you would find elsewhere, even if you take out the basic features. There are three power settings: 45W, 80W and 135W. However, even the most powerful model won’t be able to match what we have seen. The unit uses less than 50w per foot to operate, which puts it on par with an ordinary lightbulb. LightHouse claims that it uses 25% less energy than most tube heaters. This is a great investment if you are looking to save money and only need a small amount of heat.

Because of its size and efficiency, many buyers find more uses for the handy device. They can dry out damp cupboards or use it as a heater in the house when the greenhouse isn’t needed.


  • Perfect for greenhouses to the size of 6×6
  • Offers a five-litre tank
  • High-quality product
  • One tank normally provides 80 hours of burning

The compact size and the amazing design are the first things you notice when you first look at this product.. Which means it’s more suitable for small spaces. A larger greenhouse may limit the heat generated by the device.

The heater has a 5-litre capacity and can burn for up to 80 hours with just one fill. Fireside’s beautiful design allows us to have threaded chimneys and brass-plated twin burners. It measures in at around 300mm by 400mm. However, its size isn’t too big.

This heater needs premium paraffin to work effectively. It is available in all 50 states. Amazon and other websites sell paraffin, so you can get everything you need in one transaction. The additional features such as frost-free protection make this a great investment.


  • 2kW of power
  • Controlled via a thermostat
  • Boasts ‘Oxygen Depletion System’

2kW is the ideal power for greenhouses at home. The model is made in Europe and meets all the European standards. This should give you confidence in its design and performance. Manufacturers promise high performance, reliability, and durability.

This unit allows you to control the temperature in the greenhouse using a thermostat. This means that it won’t get too cold in winter. The product also includes a hose, Piezo ignition and a 37 Mbar regulator oxygen depletion system.

The unit measures 485mm in total and has a width of 300mm, and a depth of 130mm. The unit can be tucked into a corner or out of sight so that it doesn’t pose a risk to anyone who enters the greenhouse. Propane is required for the unit to function properly. This can be easily found across the country.


  • 12V solar fan with three different speed settings
  • 20W monocrystalline solar panel
  • Ideal for greenhouses as well as sheds
  • Many actually find use when camping or spending time in a caravan
  • Can be powered using a 12V battery

This portable solar fan will keep your plants and vegetables warm no matter how cold outside. It is lightweight at just 39cm in height and weighs just one kilogram. This makes it easy to transport, whether you are camping or just need to keep warm while on holiday. The model has an oscillating grill that ensures the air is distributed evenly. There are three airflow speeds to suit your needs, whether you need low, medium or high.

The monocrystalline solar panel will provide power of 20W and a device that is suitable for all types of weather. You have a device that won’t get damaged by rain, and it will last for years. The frame is made of strong aluminum, so you won’t have any issues with wear or damage.

There are many great features on this unit. However, the best feature is that it can be run with a 12V battery. The whole unit can be run on a 12V battery if you have one already or you spend a little more.

Real Men Sow
Real Men Sow

Hello, I’m Pete and I’m currently based in the west of Scotland, in a small place called Rosneath, where I’m exploring my garden adventures. I personally started gardening around 6 years ago and initially, I started out by growing my favorite fruits and berries, such as strawberries, Raspberries & Gooseberries. Since then I’ve added a lot of vegetables and working closely with my neighbor, it’s been a lot of fun.