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The Ultimate Guide to Grow Room Controllers

Harvest Integrated


How to Create Consistent Grow Environments With Grow Room Controllers

The grow room environment is one of the most important aspects of an entire grow operation. High yields, high product quality, and ultimately, the success of the grow are all hinged on having the ideal environment. 

But achieving the perfect environment can be difficult. Keeping up with elements such as lighting, temperature, airflow and humidity, plus manually adjusting them can quickly become arduous and time-consuming. Be that as it may, there’s a solution to this problem and it’s called grow room controllers. 

This guide will give you a comprehensive rundown of these controllers. From what they are to how they work and how you can use them to create a consistent grow environment.  

What is a grow room controller?

At the most basic level, a grow room environment controller allows the grower to automate the growing process. Using a combination of controllers, a grower can monitor and control the different aspects of plant health including heat, humidity, moisture, lighting and nutrients. 

A grow room controller also gives the grower more time away from the grow room – the grower just needs to set the controllers to the ideal range and leave them to do the work. This is an important function of grow room controllers because it reduces the risk of human error. Since human error is a common cause of grow room problems, it follows that environment controllers help to reduce common grow room problems drastically. 

Grow room controllers usually come with their own set of sensors to track the grow environment, but they can also be connected to existing grow room systems. 

Types of grow room controllers

There are several types of grow room controllers on the market. These range from single-function controllers that control only one environment aspect to multi-function controllers that monitor several aspects. The following are some common types of grow room controllers:

Lighting controllers

An indoor grow lighting system mimics natural sunlight to help plants grow. As such, the lighting system should function reliably, i.e. it should turn on and off at the correct intervals. Lighting controllers allow you to set how long you want grow lights to run in order to ensure optimal plant development. 

Temperature controllers

Similar to lighting, temperature sets the stage for proper plant development. For example, seedlings need higher temperatures to allow them to absorb more moisture out of the air. If the temperatures are not kept within a range that allows this to happen, there is an increased risk of mold, mildew and pests. As the plants continue to develop, grow room temperatures need to be adjusted accordingly to simulate the changing seasons and help with flowering. 

Temperature controllers ensure that temperatures stay within the ideal range. They are especially important when it comes to managing daytime and nighttime temperatures since temperatures are lower when grow lights are off. Some temperature controllers work on the same cycle as the grow lights, turning off fans at nighttime to maintain the perfect conditions. 

Humidity controllers

Humidity works together with temperature to create the perfect growing conditions for plants. As with temperature, plants have an ideal humidity at each stage of their growth. For instance, humidity tends to be higher during propagation than when plants develop a root system or during flowering. If humidity levels are lower than required, the plants may take up too many nutrients, resulting in nutrient burns. Conversely, if humidity levels are too high, there will be excessive moisture which contributes to pest invasion as well as the development of mold and mildew.

Humidity controllers measure the moisture levels in grow rooms and adjust them accordingly. They do this by powering on/off the humidifiers and dehumidifiers, all without requiring you to be constantly stuck in the grow space. 

CO2  controllers

Carbon dioxide (CO2) can be very beneficial to plants, particularly cannabis. When combined with ample grow lighting, supplementing cannabis plants with CO2 can reduce the time to harvest and increase yields. 

As with all elements in the grow room, CO2 has to be kept at the right levels to reap its benefits.  A controller helps you do this by keeping CO2 at a safe level. Without a CO2 controller, you’ll be stuck manually turning on/ off the equipment, and that is just not efficient. 

Ventilation controllers

A good grow room ventilation system ensures that plants always have fresh air. Additionally, a good system plays a big role in controlling odors and it ensures that humidity, temperature and CO2  levels stay within the desired ranges. Considering how crucial all these elements are to the grow space, it’s easy to see how important ventilation is. Nonetheless, grow room air typically needs to be exchanged every 3-5 minutes, so it goes without saying that you need some way to control this. 

Ventilation controllers allow you to set ventilation intervals and many of them allow you to turn the fans on/off in accordance with the grow lights. They also let you control the power of your fans; you probably won’t need fans blowing at the same level at night as during the day due to temperature changes. With ventilation controllers, you’ll be able to set different fan speeds depending on the time.

Irrigation controllers

Plants need water for multiple functions including cooling, photosynthesis and transporting nutrients. However, the water levels have to be kept right. A plant with roots growing in waterlogged soil cannot absorb the oxygen it needs. This leads to root rot, which affects nutrient and water uptake, and may cause the plant to die. Underwatering, on the other hand, typically results in slow plant growth. The plant may fail to flower, and in extreme cases, it may eventually die. 

Irrigation controllers can help you create a customized water schedule. With them, you can set when and how much water is provided to your plants. The automatic watering schedule means that plants can receive the required amount of water to remain healthy without the risk of under or overwatering. 

Nutrient and pH controllers

Like animals, plants need nutrients. Nutrients help plants to reproduce, germinate, grow and fight off pests and diseases. You’ll need to provide plants with the correct nutrients if you’re going to avoid stunted plant growth or the death of plant tissue. You’ll also need to get the pH right. This is because pH has a significant effect on the plant’s ability to access essential nutrients. 

Nutrient and pH controllers allow you to optimize nutrient levels while maintaining pH to achieve maximum yield. Nutrient controllers let you create nutrient blends according to your plants’ specific needs. This way, you can deliver precise doses of essential nutrients to the plants. pH controllers allow you to measure, monitor and adjust the level of your water and growing soil pH level.

Multi-function Grow Room Controllers

Sometimes you may need a specific controller to help fix a particular problem in the grow room. However, using separate controllers for different elements (e.g. humidity, ventilation, temperature and CO2) can get messy. If you find yourself needing multiple grow room controllers it may be time to consider a comprehensive solution. 

This is where multi-function grow room controllers come in. They are designed such that you can manage multiple aspects of grow room environment control. The ability to control a large part or all of the growing process in a single location is a great way to improve the efficiency of your facility. 

What are the benefits of grow room controllers?

Grow room environment controllers have several benefits including:

Complete oversight of your crop

Grow room controllers offer control and oversight of your crop. You can monitor, adjust and optimize the environmental aspect you wish to control without having to do everything manually. For example, power fluctuations, temperature and humidity changes, and equipment failures can all disrupt your grow room and affect plant development. With a good control system, you can automatically keep an eye on all these different parameters and tackle any problems efficiently.

Time savings

Monitoring and adjusting environmental controls to ensure consistency can be time-consuming. Since grow room controllers do the work for you and ensure that the environmental controls work well together, you have time to focus on other aspects of your operation. 

Increased efficiency

Lighting, temperature and humidity control, irrigation, and air quality control combine to account for a significant portion of total grow room energy consumption. Automating the control of these elements and introducing a high level of precision can lower energy expenses. One study found that a dynamic control system that lowers temperatures in the morning can lead to a 25%-40% reduction in energy costs without any loss of plant quality and with no major investments. 

Grow room controllers can also schedule timers for preventative maintenance so that your equipment gets proper downtime. This is particularly useful since it helps prevent blowouts that lead to loss of productivity.  Ultimately, environment controllers increase efficiency and savings – you don’t have to worry about overusing resources to achieve the optimal growing environments. 


Grow room controllers are typically scalable. They allow you to expand your facility while maintaining the control parameters and automation.  

Game-changing data

Environment controllers can track data, giving the grower insight into which combinations of environmental factors promote optimal plant growth and the highest yields. Over time, the data can be leveraged to maximize output, minimize operating costs and make effective use of resources. 


The automation of several aspects of grow room environmental control is cost-effective in the long run. The more processes you automate, the less labor you will need to support your grow space and the fewer productivity lulls you will experience. Since labor is one of the costly aspects of many operations, reducing labor costs and productivity issues will help boost your bottom line. 

Who needs a grow room controller?

Being able to control and monitor the environment is vital for the success of every cultivation facility. While environment controllers may be unnecessary for backyard farming, they are an essential component for a variety of larger growing environments. 

Grow room controllers are beneficial when growing all crop types, including cannabis, and they can be adjusted to fit the cultivation style of each crop. They not only ensure that you’re able to accurately track and monitor your crop’s growing environment, but you can take the insights and replicate them to improve subsequent growth cycles. 

Which is the best grow room controller? 

There isn’t one grow room controller that works for every grow. The best controller for your facility will be the one that meets your needs and adds value to your grow setup. While many focus on cost, it’s important to take into account which controller will integrate with and enhance your facility the most. 

For example, some controllers need only a few sensors and an app to integrate into an existing system while others require an investment of large monitoring devices. Likewise, some spaces require large controllers and others need small ones. It makes no sense to have a large grow room controller that is underutilized in a small grow space. Finding the right grow room controller will help you attain your fullest growth potential.

Factors to consider when looking for a grow room controller

The climate control market is growing fast, especially when it comes to controllers that are dedicated to cannabis grow rooms. The availability of many products on the market can make choosing the right one daunting so consider the following factors as a starting point for choosing the right solution. 

Ease of use: Think about how easy the controller is to use. Depending on your experience with grow room controllers, choosing a controller that is relatively hard to use can be counterproductive. Some controllers are plug-and-play while others require more complex configuration and installation. 

Ease of use is also important when it comes to the display. An easy-to-read display will simplify how you take readings. Overriding the controllers or altering any parameters will also be relatively easier with an intuitive display.

Durability: You need to maximize the return on your investment so it’s best to choose a controller that is made of durable materials. It’s also a great idea to check for a warranty and customer reviews before making a purchase.

A robust alert system: Does your grow room controller alert you every time there is a spike or dip in the light, temperature, humidity or CO2 levels? It’s important to invest in a system that alerts you whenever the ideal environmental conditions are not met.

In the end, the factors you look for when finding a controller will be determined by your grow room requirements. This means that you should know exactly what you need before looking for a solution.

Creating ideal grow environments with grow room controllers

Grow room controllers don’t mean that you plant your crop and only come back during harvest time. You can’t automate every part of your grow room and there will always be some level of work you need to do to keep things running well. However, grow room controllers will help you cut back on the workload and human error, thereby making things a whole lot easier and transforming how you run your operation.