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Grow Room too Cold? Here’s Why & The Fix

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Cold temperatures threaten the lives of plants. To ensure that your plants in the grow room withstand cold seasons, you must have a plant to warm them. Plants need warmth in every stage of their growth.

Without a doubt, the coldness will find its way in your Grow room. When winter hits, it affects every life. Plants planted indoors suffer more since their mother nature is not there to fight for them.

This is why, as a grower, you need to ensure the temperatures are optimum. The good news is that there are simple ways to fix the problem of coldness in grow tents.

In this article, we will share with you simple ways to fix the plant’s temperatures and why it’s important.

Why Right Temperatures Matters for Your Grow Room

Right Temperatures Matters for Your Grow RoomTemperatures in your Grow tent should always be kept at the optimum. To get the best yields, you can’t let the temperatures to go high or low. They have to be kept under the right conditions.

Low temperatures will slow down the growth of your plants and you won’t get the best yield. Temperatures that are below 60°F (15°C) will shock or kill your plants.

On the other hand, when the temperatures are left to rise above 80°F (26°C), they will slow bud growth. As a result of high temperatures, they will become loose and airy.

Ideal Temperature for Your Plants

Different plants require different levels of warmth. But with that said, there is an average warmth that is conducive for any plant to thrive.

The need for warmth also differs depending on the phase at which you are plants are growing. Therefore, to get maximum yield from your Grow Room, ensure you keep your temperatures within the following levels.

Vegetative Phase – 70-85°F (20-30°C) 

Vegetative phase is a stage at which plant is maturing. The leaves are blossoming and branches are developing. This phase is characterized by continuous growth.

During the vegetative stage, your plants would require a higher level of warmth. Basically, you should keep the temperatures between 20 degrees Celsius and 30 degrees Celsius.

Flowering Phase – 65-80°F (18-26°C)

At the phase, your plant starts developing buds and producing yields. When your plants hit at this stage its good to lower the temperatures in the Grow tent.

Lower temperatures help plants produce the best bud color that has a better smell, density and trichome production.

During this phase, ensure there is a temperature difference of 10°F (8°C)  between the day and night. This will ensure that you get the best quality yield.

When To Expect Your Grow Room To Be Cold

Different times in the day and throughout change of seasons, you will notice changes in your Grow room temperature. This is why it’s important to always be on lookout. You will easily identify when temperatures go below normal and fix them before they affect your plants.

Temperatures will generally go down during the winter season. This is why you should have some intervention measures that can support the warmth of your Grow tent throughout the entire winter season.

Apart from the winter season, you will also notice some changes in other days.

Mostly, temperatures will rise and fall during the day. At night, you should expect them to be at their coolest levels. It’s therefore, important to always inspect and measure the temperatures in your Grow room.

Just be keen with the temperatures around you. If the room where you have placed your Grow tent is too cold, know the same coldness is affecting your plants.

The best way to test the temperatures is by buying a remote thermometer. The sensor will detect the changes in temperatures and notify you through your Android or iOS device.

When you buy the thermometer, you download an app. The system will send you alerts when the temperatures are above the desired temperatures.

The symptom of Grow Room When It Gets Too Cold

We have mentioned you can use a remote control thermometer to monitor the temperature changes for your Grow room. However, without a thermometer, you can easily tell when the temperatures are going way below the desired temperatures.

The only problem is that most of the times you will notice the changes when it’s too late and your plants have already been affected.

As a grow tent becomes too cold, you will notice some irreversible damages. As a result, the value of your plant yields decreases.

So when you notice either of the following symptoms, know your Grow room is becoming too cold, and the temperatures need to be fixed.

  • Change of yield density
  • Mold growth
  • Plants losing color
  • Change in smell, taste, and color of your yields.

Fix Cold Temperatures in A Grow Room

Fix Cold Temperatures in A Grow RoomOnce you are certain that temperatures are below the desired level in your grow room, the next thing should be to fix them.

We didn’t jump straight to the ways to fix coldness because we thought it’s important to note the things we have discussed previously.

Sometimes you might think the temperatures are low while they are still at the right levels. The increasing warmth in your grow tent when temperatures are at optimum would eventually overheat the room.

Consequently, you will suffer more damages.

However, if you have inspected and ascertained that your Grow room is getting cold, apply the following simple technique, and fix the problem.

Let’s get started.

Simple Ways to Raise Warmth in Your Grow Tent

The following are simple and proven ways to raise the warmth of your Grow room temperature. Apply these strategies, and you will notice a great difference in the performance of your plants.

1. Interchange Your Lighting Periods

Normally, you will have your lights on during the day and leave off during the day time. This is a common practice during the summer.

The main reason why you opt to keep the lights on during the night its because during the day, there is more heat coming from outside during the summer season. When you leave the lights on they will increase the heat and eventually affect the growth of your plants.

However, during the winter season, this should be a different case.

During the day time, the temperatures are relatively low. But during the night, they tend to be extremely high.

So, one of the best ways to deal with this coldness, is to interchange your lighting schedule.

Put on the lights during the night. And during the day put them off. At night, they will provide your plants with additional warmth.

However, don’t fall under the trap of leaving your lights on during the day and night. Your plants need some hours of darkness for them to bloom well.

When plants are at the vegetative stage, you can leave the lights operating for between 18 to 22 hours a day. This will help the plant do well in maturing their leaves and other parts. But during the flowering phase, ensure the lights are kept at a minimum.

This tip works best during the vegetative phase of your plants.

Sometimes the light intensity in your grow room might not be in a position to add additional heat. In this case, it’s advisable to install additional lights to your grow tent.

To get the best results, consider buying a Fluorescent Grow bulb instead of LED lights. These ones produce a higher amount of heat.

T5 Grow Light (2ft 4lamps) DL824 Ho Fluorescent is the best bulb to buy in this case. With its features, the lighting system will give you the best performance.

2. Install Heating Systems

The heat produced by your lighting system won’t be sufficient. It’s a temporary solution as you get a permanent fix.

One of the best ways to deal with coldness is having heaters.

Just like any other room, during winter seasons, you have to get air conditioners. For your grow room you need a good performance Grow room heating system.

3. Use a Tube Heater

In the market, you will find tube heaters originally designed for greenhouses. These heating gadgets will give you an affordable heating solution. They spread heat in your room consistently keeping your room with a steady temperature increase.

Star HE-197829 Qtz 120V-350W60V Htrtbe is the best heater you will find in the market. When installing over your grow room, it will do an excellent job.

4. Use Thermostat Radiator

Alternatively, you can choose to buy Oil Filled Radiators. Unlike the tube heaters, these radiators are thermostatically controlled. The radiators have a compact design that ensures they don’t occupy much space when placed in your Grow room.

The best thing with them is that you can easily control the temperatures to get optimum performance. In short, its save, and it won’t cause any detrimental effects in your plants.

We recommend you to buy Ideal-Air Pro Series Mini Split 36,000 BTU  for heating your grow tent. This is a digital thermostat radiator. It’s perfect for placing in your grow room from the germination phase of your plants.

Grow Room too Cold

5. Use a Fan Heater

This is another option for heating your cold Grow room. However, this heater should only be used in a growing area with high humidity.

The heater releases dry, hot air that will definitely lower humidity. Low humidity damage your plants.

Read our article and learn how to raise the humidity in the Grow room if this is a concern to you (Link this article here).

With that said, this fan works well. For effectiveness, place the fan outside the grow room and connect it with the ducting system of your tent.

But if you choose to place it inside your grow tent, ensure it’s not directed to the plants.

6. Warm Nutrients With Aquarium Heater

This is a perfect idea for warming up nutrients for your plants. When temperatures go down in a Grow room, the roots suffer also. They become cold. As a result, they don’t take up minerals and water as required.

Heating your water is necessary for growers who have planted their crops in media-less systems – growing without soil. The reason why you need heating in such cases because the roots in such conditions do not have proper insulation that protects them from harsh conditions.

To solve this problem, you need to heat your nutrient solution before adding it to your growing systems.

Get a different container where you mix your nutrients. After that, warm them up. An aquarium heater will do this job perfectly.

However, ensure the nutrient solution is not hot. It should only have room temperature. Hot solution will burn the roots of your plants.

Our Recommended Heating System For Grow Rooms

We recommend you to buy Ideal-Air Pro Series Mini Split 36,000 BTU  for heating your grow tent. This is a digital thermostat radiator. It’s perfect for placing in your grow room from the germination phase of your plants.

7. Use Soil Mats to Warm the Soil

In most cases, when the temperatures go down, most farmers think about the air alone. Only a few people care about the warmth of the soil – which is very important.

When the grow room becomes cold, the soil becomes cold too. As a result, it makes it difficult for the plants to obtain nutrients and water from the soil.

Sometimes water and other minerals condense making it even more difficult for roots of performing as expected. Here is where the soil mats come in.

The soil mats are effective in heating the ground, especially during the germination stage. Seeds require an amount of warmth for them to germinate normally. In fact, most people think these mats are only useful during germination. But the truth is the mats can be used at any time to give warmth to the soil.

When it comes to heating your soil, we recommend that you buy VIVOSUN 10″x20.75″ Seedling Heat Mat. It’s an amazing mat that will keep your soil warm.

Final Verdict

Every time you need to get the best out of your Grow room, you need to maintain all conditions at optimum. Your focus should be to ensure that nothing is lacking or supplied in excess. Otherwise, you won’t get the yields needed for your Grow tent.

Warmth is one of the most critical part of your plants’ growth. From germination to harvesting, you need a certain amount of warmth for your Grow tent. That’s why it’s important to ensure that you keep the temperatures at optimum.

The good news is that there are simple ways to apply in your grow tent that would ensure the warmth is kept at the optimum.

Most importantly, ensure you buy quality equipment for maintaining warmth in your grow room. With no doubt, buy any equipment we have recommended in this article and you will get amazing performance.