How can I increase heat in Grow Tent?

Controlling heat in the grow room is one aspect of growing marijuana indoors that can be difficult for many of us growers. You may be happy with you best led grow light, however, grow lights provide our plants with lots of life-giving light, but they also produce heat, and big grow lights can produce a lot of heat!

Most cannabis plants start suffering when their temperature gets over 80-85°F (27-30°C), so it’s important to keep your grow space below that threshold. This tutorial will teach you tactics that you can use to control temperature and fix heat problems. You’ll also get some tips to help make sure your cannabis plants do great even if it gets too hot!

Placing a thermometer and acknowledging the best comfortable temperature range is the best way to identify a ‘too cold’ grow space. Apart from that, check for these following symptoms as well-

• Small and Weak Growth.


• Damp areas and unwanted mould.


• Chilled out root systems(Hydroponics).


• Bad taste, smell, color or density of grow plants.

The ideal temperature to maximize your plants growth potential is between 20 degrees Celsius (68 Fahrenheit) and 28 degrees Celsius (82 Fahrenheit). Temperature can definitely fluctuate without much (or any) damage to your crop. It is the extended temperatures of too cold or too hot that will stunt or kill your marijuana. Don’t let the inside of the tent get any lower than 20 degrees Celsius (68 Fahrenheit) and definitely no higher than 31 degrees Celsius (87.8 Fahrenheit).

If the tent gets to these temperatures, make sure to remedy the situation as soon as possible. Even though space heaters and oil radiant heaters have thermostats on them, it is a very good idea to have a separate thermostat in the room, placed on the opposite side of the room.

You can expect the area where the heater is to get hotter when it is first running and the heat hasn’t spread around the room yet. So, having a thermostat close to the heater might give false readings.

Now let’s look at the brighter part of the article. From right here, we’ll be talking about some hacks and solutions to raise the temperature to an expected level.

But before you decide to spend any bucks to solve the low-temp issue, consider these few hacks that might lead a way out of it-

You’re already dealing with a cold temperature inside your grow room. So, you never want the heat fly away before it reaches the plants and nutrients. And the best possible way to make it happen is to Insulate the space as much as possible.

Now, insulating a grow space doesn’t only mean to duct the airflows. Here is a complete list of insulation works you need to do-

• If you’re growing in pots, wrap Aluminium Foil Sheets around them.


• If the pots are in direct contact with the cold floor, put a Polystyrene Plastic Sheet in between.


• Wrap the whole grow tent from outside, leaving no way out for the heat to fly away.

Let’s say your plants are in vegetative development, or not sensitive to photoperiods. In both cases, you don’t really have to keep a heater plugged in to deal with the cold snap. Instead, it’s better to use as many full spectrum LED grow lights as possible.

Now, you may raise an eyebrow on running grow lights for 24 hours a day. But the truth is, that will cost less electricity than even 5-6 hours of heater runtime. Moreover, some power supplier companies provide cheaper electricity during the night time.

You’re about to do something to generate more heat inside the grow space. But what if the heat doesn’t reach the plants and ends up creating hotspots instead?

Make sure to circulate the heat around the entire space. Some heaters come up with circulation method of their own, like a inline duct fan. But for many of them, you have to circulate them internally. The best way is to use a standby fan.

One of the reasons for a low temperature is lack of warm intake air. And that’s because the intake air is imported from a place that’s not so warmer then grow space itself. Trying to solve the issue may raise the minimum temperature of your grow room.

For sake of proper ventilation, you must keep a couple of intake and extraction fan turned on. Usually, that’s no problem as you have internal heating sources like grow lights and heaters. But what if the lights are turned off? Should the extractor fan be switched off to trap the heat inside?

No. But you must try to minify the fan speed. Connecting the extractor fan with a Day/Night Fan Speed Controller is the best choice here. Once you set the temperature limits of day and night, they’ll control the speed automatically based on whether the lights are on or off.

You might be suffering from not only a chilled up grow space, but also chilled up nutrient solutions. The damage that a cold nutrient solution can cause to your plant is severe.

As a solution, you may try increasing the nutrient strength by 20%(or so), so that the plants may intake the necessary nutrients without as less water as possible. Eventual, the effects of low temperature on the plant’s health will be minified a lot.

Warning: Remember, plants transpire less in a chilled condition. So commercial growers may have to compensate for increasing the nutrient strength.

It may sound weird, but we’re pointing to a method that warms up the composts and turn them into heat sinks. As your tent is likely to chill at night time, storing some heat inside the compost piles is a great idea.

The process is simple. Create a trench in a place which is warm during the daytime. Let the daylight heat up the compost piles and they will release the heat later in the night. Just chose the place of heating composts carefully.

Now that you have read this article, you should have a good idea on how to heat your grow tent. I have provided you with some excellent options. Out of all of them I prefer the space heater. Just remember that you might want to ventilate the room as well. This is a good idea not only for dispersing heat but for clearing out the smell of the weed. You can also hook up a charcoal filtration system to clean out the scent. There are many type of grow light, such as LED、HPS grow lights, you can know more with their heat output and choose one suitable for your grow room!

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Controlling heat in the grow room is one aspect of growing marijuana indoors that can be difficult for many of us growers. You may be happy with you best led grow light, however, grow lights provide our plants with lots of life-giving light, but they also produce heat, and big grow lights can produce a lot of heat!

Most cannabis plants start suffering when their temperature gets over 80-85°F (27-30°C), so it’s important to keep your grow space below that threshold. This tutorial will teach you tactics that you can use to control temperature and fix heat problems. You’ll also get some tips to help make sure your cannabis plants do great even if it gets too hot!

Placing a thermometer and acknowledging the best comfortable temperature range is the best way to identify a ‘too cold’ grow space. Apart from that, check for these following symptoms as well-

• Small and Weak Growth.


• Damp areas and unwanted mould.


• Chilled out root systems(Hydroponics).


• Bad taste, smell, color or density of grow plants.

The ideal temperature to maximize your plants growth potential is between 20 degrees Celsius (68 Fahrenheit) and 28 degrees Celsius (82 Fahrenheit). Temperature can definitely fluctuate without much (or any) damage to your crop. It is the extended temperatures of too cold or too hot that will stunt or kill your marijuana. Don’t let the inside of the tent get any lower than 20 degrees Celsius (68 Fahrenheit) and definitely no higher than 31 degrees Celsius (87.8 Fahrenheit).

If the tent gets to these temperatures, make sure to remedy the situation as soon as possible. Even though space heaters and oil radiant heaters have thermostats on them, it is a very good idea to have a separate thermostat in the room, placed on the opposite side of the room.

You can expect the area where the heater is to get hotter when it is first running and the heat hasn’t spread around the room yet. So, having a thermostat close to the heater might give false readings.

Now let’s look at the brighter part of the article. From right here, we’ll be talking about some hacks and solutions to raise the temperature to an expected level.

But before you decide to spend any bucks to solve the low-temp issue, consider these few hacks that might lead a way out of it-

You’re already dealing with a cold temperature inside your grow room. So, you never want the heat fly away before it reaches the plants and nutrients. And the best possible way to make it happen is to Insulate the space as much as possible.

Now, insulating a grow space doesn’t only mean to duct the airflows. Here is a complete list of insulation works you need to do-

• If you’re growing in pots, wrap Aluminium Foil Sheets around them.


• If the pots are in direct contact with the cold floor, put a Polystyrene Plastic Sheet in between.


• Wrap the whole grow tent from outside, leaving no way out for the heat to fly away.

Let’s say your plants are in vegetative development, or not sensitive to photoperiods. In both cases, you don’t really have to keep a heater plugged in to deal with the cold snap. Instead, it’s better to use as many full spectrum LED grow lights as possible.

Now, you may raise an eyebrow on running grow lights for 24 hours a day. But the truth is, that will cost less electricity than even 5-6 hours of heater runtime. Moreover, some power supplier companies provide cheaper electricity during the night time.

You’re about to do something to generate more heat inside the grow space. But what if the heat doesn’t reach the plants and ends up creating hotspots instead?

Make sure to circulate the heat around the entire space. Some heaters come up with circulation method of their own, like a inline duct fan. But for many of them, you have to circulate them internally. The best way is to use a standby fan.

One of the reasons for a low temperature is lack of warm intake air. And that’s because the intake air is imported from a place that’s not so warmer then grow space itself. Trying to solve the issue may raise the minimum temperature of your grow room.

For sake of proper ventilation, you must keep a couple of intake and extraction fan turned on. Usually, that’s no problem as you have internal heating sources like grow lights and heaters. But what if the lights are turned off? Should the extractor fan be switched off to trap the heat inside?

No. But you must try to minify the fan speed. Connecting the extractor fan with a Day/Night Fan Speed Controller is the best choice here. Once you set the temperature limits of day and night, they’ll control the speed automatically based on whether the lights are on or off.

You might be suffering from not only a chilled up grow space, but also chilled up nutrient solutions. The damage that a cold nutrient solution can cause to your plant is severe.

As a solution, you may try increasing the nutrient strength by 20%(or so), so that the plants may intake the necessary nutrients without as less water as possible. Eventual, the effects of low temperature on the plant’s health will be minified a lot.

Warning: Remember, plants transpire less in a chilled condition. So commercial growers may have to compensate for increasing the nutrient strength.

It may sound weird, but we’re pointing to a method that warms up the composts and turn them into heat sinks. As your tent is likely to chill at night time, storing some heat inside the compost piles is a great idea.

The process is simple. Create a trench in a place which is warm during the daytime. Let the daylight heat up the compost piles and they will release the heat later in the night. Just chose the place of heating composts carefully.

Now that you have read this article, you should have a good idea on how to heat your grow tent. I have provided you with some excellent options. Out of all of them I prefer the space heater. Just remember that you might want to ventilate the room as well. This is a good idea not only for dispersing heat but for clearing out the smell of the weed. You can also hook up a charcoal filtration system to clean out the scent. There are many type of grow light, such as LED、HPS grow lights, you can know more with their heat output and choose one suitable for your grow room!