Top 6 Best Indoor Heaters ( 2023 Reviews)

When winter comes, as a responsible and educated marijuana grower, you should know that the needs of your plants will change. Among others, the low temperature can make the external environment uncomfortable and can hinder the growth of the plant. That being said, the best way to address the change in temperature would be through the use of the best indoor heaters in a grow room.
The average temperature for growing cannabis should be between 21 to 29 degrees Celsius. If it becomes lower than the required temperature, this is the time you should start using a heater. However, with too many options that are available, you will most probably end up being confused. To help you decide, keep on reading the rest of this post and we’ll let you know some of the best products to take into consideration.

Best Ceramic Heater

#1 Lasko 6435 Ceramic Oscillating Heater Review

With the design of this product, it won’t just make an excellent ceramic heater for the grow room, but even in any room in the house. At its size, this will also be good enough for a large grow room. One of its best features is the oscillation, which will allow it to provide full heating coverage regardless of the size of the grow tent where it will be used.
The multi-function remote control is also a plus. There is no need to open the door of the grow room to make adjustments on the heater. As for the control panel, there is an electronic touch control display on the top of the unit. For versatility, you will be able to choose from three heat levels – high, low, and auto. It also comes with a 7-hour timer and 2 quiet settings.
The heating capacity of the unit can be attributed to its 1500 watts of power.
Lastly, it comes with a three-year warranty from the manufacturer.

Q&A: Do you put it inside the tent or outside the tent?

This will depend on the size of the tent that you have. Because of the large capacity of the heater, it will be best to use it outside with a fan. Depending on the material of the tent, the heat in the entire room produced by the ceramic heater can penetrate inside the grow tent.

Q&A: Is this a loud fan?

The loudness of the fan is going to be subjective. Generally, it is quiet. There are even two quiet settings. It is like a normal fan with a whooshing sound, which is nothing that you will find disruptive.

Best Oil-Filled Heater

#2 Delonghi EW7707CM Safe Heat Oil-Filled Radiator Review

Equipped with 1,500 watts of heating power, it is safe to say that it is the most powerful from the indoor heaters that are mentioned in this post. Even if you have a big grow room, there is no need to worry as it can provide more than enough heat.
With the oil system of this heater, one thing that you can enjoy is the fact that it is maintenance-free. You can expect that it will withstand the test of time without requiring too much on your end.
For versatility, it comes with an adjustable thermostat and multiple pre-programmed settings, which will allow you to customize the heat based on the needs of the grow room.

Q&A: Can you leave it on 24/7?

Yes, you can leave this heater turned on round the clock. There is no need to worry that it will overheat or explode. It has Safe Heat feature which allows it to turn off on its own to prevent overheating. However, you need to monitor the conditions in the grow room as prolonged exposure to extreme heat, even during the winter, can end up damaging the plant.

Q&A: What is the coverage of this heater?

The coverage is bigger than most of the heaters that are mentioned in this post. According to many of its users, it will be good enough for a grow room that is 12 x 12 feet.

Best Propane Heater in Grow Room

#3 Mr. Heater F274830 MH18BRV Indoor Propane Heater Review

This is a heater that comes in a variety of designs with a heating power that ranges from 4,000 to 18,000 BTU and perfect for a room that is up to 300 square feet. If you have a small grow room, choose the one with the lowest heat setting. You will have the opportunity to control the heat through the knob that is strategically positioned. You can choose from low, medium, and high heat settings.
For your safety, the propane heater has an automatic shut-down feature. It will turn off on its own when it accidentally tips or when the oxygen level detected is low.
With the default setup, it can be connected to a one-pound propane cylinder. On the other hand, if you use an optional hose, you can connect it to a 20-pound cylinder.
The product comes with a three-year warranty from the manufacturer.

Q&A: Is it safe for indoor use?

As the manufacturer specifies, this is one that is made specifically for indoor use. However, it is important that you have the right ventilation for the air to circulate. Even in a grow tent, this is important so as not to cause negative impacts to the plant. It is a clean-burning heater and there is no need for an outside venting.

Q&A: Does it produce a foul odor?

One of the most important concerns with propane heater is the foul odor that it can produce. The gas can be unpleasant. For this model, however, there is no need to worry. If you smell something bad, check for propane leaks.

Best Tube Heater for Grow Tent

#4 Eco-Heater 1000mm Slimline Greenhouse and Shed Heater Review

This low-cost and energy-efficient tube heater is another option that you should take into consideration. Despite being affordable, it will be effective in improving ambient heating, frost protection, prevention of dampness, and prevention of condensation, among other things.
One of the best features is the built-in thermostat, which is also the reason why it uses minimal energy. This automatically turns off when the right level of heat has been reached, allowing it to save energy.
It is also a favorite of many people because it is compact. Even if you have a grow tent with limited space, this will be more than enough.

Q&A: Is this heater waterproof?

It should be noted that this heater comes with an IP44 rating, which means that it can resist sprinkles of water. Nonetheless, take note that it is only water-resistant and not waterproof.

Q&A: What position can it be mounted?

One thing that you will enjoy with this heater is its versatility. This is because you can install it both horizontally and vertically. You can have it positioned any way you want as long as you can access the control, which you can find on one end of the tube.

Best Heating Mat for Seedlings

#5 Vivosun Durable Waterproof Seedling Heat Mat Review

Many of the users of this heating mat have reported that it can deliver up to 100% germination rate. Even for clones, it can improve rooting significantly.
Among others, one of the most notable features of this product is the alloy nikrothal heating wire, which allows the delivery of consistent heating performance and also the one that is responsible for its longevity. Aside from the multi-layer construction of the wires, it also has PET film to provide insulation, making sure that it won’t end up burning the plants even if you leave it turned on round-the-clock.
It should also be noted that the heating mat comes with the IPX4 rating for water resistance. It can resist spills and you can scrub it with water when cleaning but you cannot have it completely submerged in water.

Q&A: What is the wattage of this heat mat?

Based on the technical specifications from the manufacturer, the heat mat is only 18 watts. This means that it won’t consume too much energy while still being able to provide the right level of heat that the marijuana will need.

Q&A: Does it come with a temperature controller?

Unfortunately, the heating mat does not come with a controller. You need to purchase it separately from the kit. For the best outcomes, it is recommended that you buy the temperature controller that is also produced by Vivosun.

Best Heat Lamp for Plants

#6 Phillips 416743 Heat Lamp Review

This is a clear flood light bulb with a power of 250 watts. While it is commonly used in the bathroom or as a task lighting, this will also be good for a grow room or a greenhouse. It uses the innovative infrared technology to produce the heat that the plants will need when the temperature gets low.
The average lifespan of this light is 5,000 hours.

Q&A: What is the base type of this light?

This light comes with an E26 base, which is the standard socket used in light bulbs. This makes the installation a lot easier.

Q&A: Is this for the vegetative or flowering stage of marijuana?

Based on the technical specifications from the manufacturer, this light comes with 2700 kelvins. This means that the light is soft white and low kelvin, which is ideal during the flowering stage of the plant. If you are looking for a lamp that can be used during the vegetative phase, look for lights with 5000K to 6500K.

Benefits of Using an Indoor Heater

One of the most important elements with an impact on the growth of plants in an indoor environment is the temperature. To be specific, it plays a role in photosynthesis, seed germination, and the development of flowers. If the temperature is too high or too low when compared to the recommended range, the plant can end up suffering from a number of problems. This is exactly the reason why the use of a heater is needed during the winter season or if you live in a place that is too cold for the environment that is suitable for the cannabis.
If the grow room is too cold, one of the problems is that it can slow down the growth of the plant. This gives you a good reason to use an indoor heater. If the temperature reaches 55 to 60 degrees Fahrenheit, not only that the growth will slow down, but it can also lead to eventual death of the plant.
The marijuana can also be susceptible to mold if the grow room is too cold. Mold will affect the quality of the harvest and will put all your effort into waste as it will make the marijuana useless.

The Best Temperature for a Grow Room

It is important that you are aware of the ideal grow room temperature, which will allow you to determine when there is already a need to use a heater.
Take note that the grow room temperature should depend on the stage of the growth of the plant. You need the grow room to be a bit warm during the vegetative stage. At such point, the recommended temperature is from 70 to 85 degrees Fahrenheit, which is roughly 20 to 30 degrees Celsius.
Meanwhile, when the plant reaches the flowering stage, you can slightly lower the temperature at an average range of 65 to 80 degrees Fahrenheit, which will be about 20 to 26 degrees Celsius.
It should also be noted that the temperature should change depending on whether it is day or night. Generally speaking, you need to have an average of 10 degrees of difference from nighttime and daytime grow room temperature.
As for the clones, the temperature should be maintained at 70 to 85 degrees Fahrenheit. The clones would prefer a humid grow room and transpiration is critical to have the water that will be needed for their roots to develop. A temperature that is slightly warm will be needed by clones, similar to the vegetative phase, which makes it important to have a heater to fight the cold.
To make sure that the temperature is right, you need to invest in an accurate gauge that will eliminate guesswork on your end.

Types of Indoor Heaters to Use

In this section, we will have a quick look at some of the most common types of heaters and how they will work to adjust the ideal temperature in a grow room.

Ceramic Heater

This is one of the main categories of electric heaters. There are two main types of ceramic heaters. The first one is a radiant ceramic heater and the second one is a convective ceramic heater. Convection heat is the most common as it heats up the entire room where it is placed. In contrast, a radiant ceramic heater will heat up only the object where it is directed at.
One of the main benefits of ceramic heaters is that they will quickly heat up the room. They also cool off quickly after being turned off, which means that heat won’t linger for a long time.

Oil-Filled Heater

This type of indoor heater looks like a traditional radiator. It has fins that are filled with oil and they are heated to increase the temperature in the grow room. The oil is warmed every time the unit operates and will never burn or ask for a replacement. They also do not produce combustion gases.

Propane Heater

If you want a more powerful option for an indoor heater, you will never go wrong with a propane gas heater, which can easily heat even a large grow room. Nonetheless, you need to have venting to prevent the plant from suffering from serious problems caused by the emissions from the heater.

Tubular Heater

If you have a small grow tent, a tubular heater will work perfectly. It looks like a fluorescent light and can be hung either vertically or horizontally, as long as you can easily reach the end with the controls. Despite its space-efficiency, it is effective in heating a grow tent, especially if the size is appropriate for the power of the tube heater that you are using.
Aside from ceramic, oil-filled, tube, and propane heaters, here are the alternative ways of heating the marijuana in an indoor grow room:

  • Heat Lamp: It is a lamp that produces heat that is enough to alter the internal environment and increase the temperature. Nonetheless, this can burn the foliage and cause dryness to the plant. When using heat lamps, it is important to pay attention to the distance between the lamp and the plant, the size of the grow tent, and the power of the bulb, among other things.
  • Heating Mat: As the name implies, it is simply a mat that produces heat. It is placed under the pots or the seedling trays. It can deliver an improved germination rate by keeping the temperature between 75 to 85 degrees Fahrenheit.
  • Insulation: To increase the heat in the grow room, it will also be good to consider insulation as an alternative. It seals the grow room or tent to prevent outside air from lowering the temperature. Some may also opt to grow plants in the basement to maintain a higher temperature.

Grow Room Too Cold: How to Fix It The Right Way

Obviously, as it has been discussed in this post, the best way to control the low temperature in a grow room is through the use of an indoor heater. If you feel that it is too powerful, you can place it outside the grow tent. On the other hand, if the heater is small and will fit in the tent, you have to put it inside but make sure that you set it at a temperature that is not too hot.
The location of the grow room is also important. It would be best to grow plants in the basement during the winter as it is hotter compared to the other areas of the house. Find a place that is insulated so that the temperature outside will not easily impact the plant.
Having a sealed grow room is also important. By having it sealed, the cold from the external environment will not be able to penetrate the tent, especially if it is made of a thick material.
The use of the right grow lights for a grow room is another easy way to manage the heat in an indoor environment. You can also position them closer to the plant to generate heat. However, keep in mind that putting it too close can cause stress to the plant and can have negative impacts on its health.
You will also benefit from using additional insulation to manage the temperature in the grow room. It is an effective passive heater to correct the low temperature.
To control the temperature in the grow room, here are the simple steps that you will have to follow:

  1. Use a thermometer to know the exact temperature. Find a thermometer that is built specifically for indoor grow rooms. It will be good to find one that is also capable of measuring the relative humidity.
  2. Refer to the temperature chart stating the ideal temperature in a grow room. As it has been mentioned earlier, if the plant is a clone or if it is under the vegetative stage, the ideal temperature should be 70 to 85 degrees Fahrenheit. Meanwhile, the best temperature for the flowering stage is from 65 to 80 degrees Fahrenheit.
  3. Now that the temperature has been measured, have it corrected. If it is too cold, take note of the things that have been mentioned above.

Wrap Up

With the best indoor heaters that have been mentioned in this post, we hope that you now have an idea on how to make the environment more suitable for marijuana cultivation. You can consider these products for the best way to heat basement or grow tent when the temperature reaches a level that is too low for the plant. With the heat that they generate, it will be easy to maintain the right environmental condition for the growth of the plant.