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Grow Room & Tent AC

Grow Room & Tent AC

When it comes to cannabis industry grow rooms, two of the most challenging issues for growers are fluctuating temperature and humidity. As a controlled environment, a grow room must possess the best possible interior climate to ensure that the plants thrive in ideal conditions and grow as naturally as possible. So, what does this mean in practice?

The essential principle to remember is that plants need adequate temperature and indoor humidity. When managing the climate inside your grow room, it is critical to consider these two factors. However, one thing that you should remember is that the temperature and humidity that your cannabis plants will be subject to inside your grow room will depend on the weather in the region where you live.

While you can have many options to resolve the climate issues associated with a grow room, using a ductless mini split HVAC system provides numerous advantages you can’t get from other air conditioning systems.

Here, you will learn about the most common climate challenges in a grow room environment, the various cooling options used, and the primary reasons why using a ductless mini split system is the most suitable climate control tool for a grow room.

Here are our recommended systems for grow room applications:

Why a Grow Room Requires Strict Temperature Control

Plants react differently to different temperatures. Some plants can grow even in extreme weather conditions, but, typically, high or low temperatures affect the growth and production of marijuana plants.

The best way to better grasp this idea is to understand that some plants thrive in warmer environments, whereas others naturally flourish in colder environments. When the climate is not conducive to the growth of a particular type of plant, it will stunt its growing process or even kill it.

If you own or manage a grow room, tightly controlling the interior temperature is definitely one of the most important considerations. Although cannabis can grow and flourish in many environments and climates (this is the reason why it is nicknamed “weed”), maintaining the ideal temperatures to grow cannabis plants ensures they grow as fast as possible.

The ideal temperature ranges depend on the plant’s current stage.

  • During the vegetative stage, a marijuana plant in a grow room or grow tent typically thrives at temperatures ranging between 70ºF and 85ºF.
  • During the flowering stage, the ideal temperature range decreases to 65ºF to 80ºF. Start near the top end of the temperature range during the first half, and then gradually decrease it toward the bottom end when it progresses to the second half.

To prevent stunting the growth of your plants, you should never let the temperature inside the grow room exceed 85ºF or fall under 60ºF at any stage.

How to Obtain the Right Amount of Humidity

Aside from temperature, the humidity level inside the grow room is very critical to the growth of your plants. If you live in areas where the cold weather is typically harsh, you’ll have to consider that the humidity inside your grow room will be very high.

Humidity pertains to how much water vapor or moisture is in the air. When talking about humidity, just think of water in a gaseous state that circulates invisibly in the air. Humidity affects all living things, which, of course, include plants.

A high humidity level causes the air to become saturated with water vapor. Excessive humidity levels harm your plants because they prevent them from using their stomata to absorb carbon dioxide and release oxygen. In other words, prolonged exposure to high humidity levels prevents the plant from “breathing” correctly, which risks stunting its growth.

Comparison with the human body

To give you a better idea of how this process works, compare and contrast how humidity affects the human body. Afterward, we’ll discuss why the process is similar to plants.

Remember that sweating is the human body’s natural method to regulate temperature and cool itself down. When our body perspires, our skin pores open and release droplets of water and salt. This substance is called perspiration or sweat. Sweat absorbs some of the heat from the body, regulating the interior temperature and allowing the body to feel cooler and more comfortable.

When the humidity levels are high, it means there is already too much water vapor in the air, and it can no longer absorb more. In this case, the body sweat that carries some heat evaporates more slowly than needed.

If you’ve ever wondered why the air feels “sticky” during hot and humid days, this phenomenon is the primary reason. We also feel hotter because our sweat can’t evaporate faster from our skin, causing the heat our sweat is meant to remove to remain for more prolonged periods.

In contrast, when the humidity levels are low, the body feels cooler, but the air feels drier, and we get dehydrated more quickly because the sweat in our body evaporates faster.

How the process works for plants

Essentially, the same processes apply to plants. High humidity and low humidity are both a hindrance to plants in the same way they can be a hindrance to human bodies.

How does this affect the growth of plants? As for the plants, remember that they go through a process called photosynthesis: synthesizing nutrients from carbon dioxide and water, which they need to survive.

During this process, plants absorb the carbon dioxide from the atmosphere by opening their pores in the leaves. When they do, they release some moisture or water vapor into the air. This is called transpiration, a process when the water that comes from the pores in the leaves of the plant evaporates.

You can think of it as the plant equivalent of the human body’s perspiration process. When the humidity inside the grow room is low, the amount of moisture that escapes from the pores of the plant leaves is higher.

Losing too much water this way makes the plants dehydrated. As a result, there’s a very good chance that the plants will wilt. As a natural reaction, the plants usually close their pores to prevent losing more water.

However, when the weather becomes too hot, and the pores close up, the plants have too much water vapor inside and will not be able to absorb carbon dioxide and go through their normal photosynthesis process.

When the humidity inside the grow room is high, no water can evaporate from the pores of the leaves of the plant. This causes a problem when the temperature is also high because then the plants would not be able to lose water to cool themselves.

Why a Quality Climate Control System Is Critical

As is commonly practiced, you can control the temperature and humidity inside your grow room through proper climate management. A precisely controlled climate will enable you to grow your plants no matter the weather and enjoy the endeavor all-year-round without worrying about the right season to grow plants.

Additionally, proper climate control helps you prevent the growth of bacteria, molds, and even pests that will be very harmful to the plants. Managing the climate inside the grow room means controlling the temperature and humidity to the necessary levels conducive to optimal plant growth, development, and production.

When managing the climate inside the grow room, the main challenge is to simulate the type of climate that the plants typically get outside. This means that the temperature and humidity levels inside the grow room environment must be as close to the ideal temperature of the outdoor environment where the plants usually grow and develop.

The optimal temperature and humidity levels will change as plant growth progresses; therefore, it is also critical for your climate control system to be easy to reconfigure as needed.

Typical Cooling Options for a Grow Room

Cooling the environment is one of the critical tasks to do when maintaining a grow room. On top of other considerations, having the right cooling solution determines the overall success of your climate management in your grow room and ensures the health and productivity of your plants and crops.

When choosing the right cooling system for your grow room, don’t forget to consider its size (square footage, ceiling height, etc.). This data is necessary to help you choose a grow room HVAC system with the correct size and BTU capacity for your needs.

When you go out in the market to select the right cooling system, you will find that you can have too many options and data points to search through. These systems vary in type, size, efficiency, capacity, and performance. Some of the most common cooling solutions that are used in a grow room are fans, dehumidification systems, chillers, and evaporative coolers.

The chillers are either water-cooled or air-cooled, and both help absorb the heat that builds up inside the grow room.

When choosing evaporative cooling systems, the choices include a solution that provides mists into the air which are meant to be vaporized, and a swamp cooler system. The swamp cooler system uses a fan that blows air into a wet medium to initiate an evaporation process, which helps drop the temperature inside the grow room environment.

Keep Your Grow Room Cool with Air Conditioners

One of the most effective climate control management methods for a grow room is to use a high-quality, energy-efficient air conditioning system. Heat is naturally the most significant concern when working in sealed environments.

In many ways, this makes air conditioning the most logical option. It will not only create the right temperature inside the grow room but will also help exhaust the heat generated by your growing equipment, such as the lighting system, pumps, blowers, generators, ballasts, and many others.

With proper air conditioning, the temperature and humidity issues will become the least of your concerns when growing plants indoors. When it comes to air conditioning systems for grow rooms, some people use portable air conditioners and window AC units, but the ductless mini split system has proven to be the most effective.

Why a Ductless Mini Split System Is Your Best Option

Ductless mini splits, which comprise an outdoor compressor unit and one or more indoor air handlers, are flexible AC units that do not require any ductwork, making them very easy to install in your grow room.

Compared with other air conditioning systems, such as a window unit or central AC system, a ductless mini split is very flexible, and you should not have any issues with it whatsoever, especially regarding the location of your grow room.

Available in single-zone and multi-zone configurations, a ductless mini split is a perfect system for your grow room, especially if your growing environment is detached from your main house where the network of HVAC ductwork is installed.

A ductless mini split can also work as both an air conditioning system and a heat pump solution. This double feature makes it ideal for a grow room, especially if you’re looking for a system that will enable you to effectively heat or cool your grow room regardless of the season or weather.

Grow rooms can also benefit from ductless mini splits’ highly advanced airflow management system. One of their powerful features is the capability to heat the room even when the weather outside drops to subzero temperature.

Moreover, ductless mini split systems have better filtration technology and are more environmentally friendly than most other AC systems. They can filter out airborne contaminants and ensure that mold, mildew, and bacteria do not develop, which is essential to the proper maintenance of the grow room.

Do You Want to Go Ductless for Your Grow Room? Start Here

Maintaining a grow room is both an enjoyable pastime and a worthwhile endeavor. Whether you’re a professional gardener or an amateur grower, you know that temperature and humidity both significantly impact the growth and development of plants that you take care of and maintain.

Thus, finding the right air conditioning system makes the most sense, especially if you’re raring to have the best growing experience without consuming too much energy, money, and other resources. To get the best selection of ductless air conditioners for your grow room, you can visit   or call us at 1-855-887-0001 for inquiries and assistance.

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