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How to Winterize a Grow Room

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How to Winterize a Grow Room Blog Feature
Amanda Ringler

By: Amanda Ringler on October 6th, 2021

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Fall is here and if you’re in the northern states, it’s already starting to get pretty cold.

It doesn’t take any time at all for the winter cold to really set in. This cold can be bad news for your marijuana grow room as this space needs a very specific climate and environment. If the grow room is too cold, it could destroy your entire crop.

Your crop doesn’t have to suffer.

We here at RetroFoam of Michigan have insulated thousands of homes, pole barns, and even some grow rooms. We understand what goes into building and maintaining a grow room, so we have compiled a list of tips to help you keep Old Man Winter out of your grow operation.

How to Winterize an Indoor Grow Room

Winter will be here before you know it, so it’s important to start planning and prepping your grow room.

Here are the areas where you will get the most benefit from winterization.

Grow Room Air Condition Unit

I know what you’re thinking “How can something that makes cold air help winterize my grow room?”

Just hear me out.

Obviously, during the summer an air conditioning unit is used to help maintain a balanced temperature during the sweltering heat. The catch here is that many growers adopt a closed room method of cultivation, which requires the use of the AC unit all year long, according to Maximum Yield.

This is because the temperature and humidity are all controlled in the contained space.

One thing to make note of is that some air conditioners aren’t designed to operate in temperatures below 50 degrees. However, you can install a low-ambient kit that can slow the unit’s compressor which will keep it from freezing, according to Maximum Yield.

Keeping Water Sources Warm

If the water source for your grow room is located outside, that means the water pumped inside is going to be cold.

That cold water can cause a serious shock to your plants and their roots.

There are two ways to tackle this – reservoir heaters or to use insulation around the water source hoses.

The reservoir heaters are a must-have for a recirculating hydro system, according to Fifth Season Gardening. That’s because you can set the temperature on the unit to ensure the water stays at a safe temperature range.

Hose insulation might require a little more work to make sure you don’t shock and accidentally kill your plants. It can work to keep the water warmer, but you will need to monitor not only the temperature of the water coming in but also the temperature of the soil to make sure there isn’t a huge difference.

Grow Room Insulation

Insulation in your grow room is really going to be key to keeping cold temperatures out.

Whether it’s an indoor grow room in your basement or an out-building, you’ll need that insulation before it gets too cold, especially in the frigid climates like the Midwest or east coast of the U.S. 

Basements get cold in the winter no matter what is happening in the rest of the house if they aren’t insulated. Adding insulation to the basement walls and rim joist can help, but keep in mind not all insulations are a good fit for a grow room.

A pole barn grow room or out-building is going to experience all of Mother Nature’s seasons without insulation. That’s because metal is a great conductor of temperature. This can be very harmful to your plants, especially in the winter.

Adding the best insulation to the walls and ceiling of this structure can make it easier to keep the cold air out.

Regulating a Marijuana Grow Room Temperature

The key to regulating your marijuana grow room temperature year-round is to create an air seal.

Cannabis Business Times recommends making sure no air is coming in due to structural integrity issues or air gaps.

No matter what the temperature is outside, this air seal will keep your grow room at the temperature and humidity you need for your marijuana to thrive. As you know, cold temperatures can be detrimental to your crop.

You can avoid this potential danger by using these winterizing tips, but there is another rabbit you can pull out of the hat. Air sealing your grow room with foam insulation can create the air seal mentioned above.

If you want to learn more about how awesome foam can be, check out the Learning Center on our website. 

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About Amanda Ringler

Amanda previously has worked as a breaking news and crime reporter, TV news producer, and editor in Flint and Detroit. Throughout her career as a journalist, she has won several awards from The Society of Professional Journalists - Detroit Chapter and the Michigan Press Association. As part of the RetroFoam of Michigan family, Amanda uses her experience as a journalist to write content that will help educate homeowners on the benefits of foam insulation. When Amanda isn’t writing, she’s spending time with her husband and rescued huskies. She also loves knitting, making art, cooking, and hosting dinner and a movie night for friends and family.