The Different Ways to Keep Your Grow Room Warm Over Winter

Growing indoors during the Winter can be a real challenge, especially for beginners. When your home drops below 50°F, your grow room will feel the chill too, and your plants will show it. Cold temperatures slow growth, disrupt nutrient uptake, cause stretching, and lead to disappointing yields. In this article, I will provide some low-cost solutions to help keep the cold out this Winter, and allow you to maintain a warm indoor growing environment.

Dehumidifiers to Reduce Humidity Levels

Cold air often leads to high humidity, which can create a perfect environment for powdery mildew and mould, especially during flowering. The last thing any grower wants is to harvest their weed and discover that their buds have a severe case of mould. To prevent bud rot this Winter, use a dehumidifier to maintain optimal moisture levels. Place the water outlet outside the tent to prevent it from shutting off when it is full, and monitor the amount of water inside the tent.

Invest in a Temperature Controller

A temperature controller automates climate management when you’re not around. You can connect your fan, heater, dehumidifier, and extractor, and the system will automatically maintain your desired temperature and humidity. All you have to do is program the device so your heater kicks in and maintains the desired temperature. They may seem expensive, but they are worth every penny and can be used in the Summer to keep your room cool.

Switch From Plastic to Fabric Pots

Fabric pots naturally insulate your plant’s roots by trapping warm air between the fabric and the soil. This helps maintain optimal root health and encourages root pruning. Plastic pots can become cold, especially if you have watered the growing medium, as the water can cause condensation to form on the surface. Fabric pots work a charm when it comes to keeping the roots cosy and warm, especially if you are using a heater or heating cables placed underneath the pots.

Heating Cables on the Grow Room Floor

Heating cables can be purchased at a low cost and are readily available in aquariums or exotic pet shops. Lay heating cables along the floor of your grow room or under trays in your seedling or cloning area. They’re available in lengths ranging from 1 m to 60 m, making them a low-cost solution for small tents or cupboard housing seedlings and clones, as well as large-sized flowering rooms. 

For smaller grow spaces, heating cables are an inexpensive and efficient solution. Once plugged in, these cables generate gentle warmth and typically use just 30–60 watts, so you will hardly notice the cost in electricity. 

Autoflowering Genetics on 20/4

If you are concerned about how cold your grow room will become during the lights-off period, consider increasing autoflower seeds with a 20-hour light cycle and 4-hour dark cycle. Doing so will not only keep your grow rooms warm during the colder nights, but it will also enable you to produce the best autoflowering crops possible, yielding the largest harvests. 

Raise Pots Off The Ground

The roots of your cannabis plants are sensitive to cold temperatures, and you would be amazed at how much of a difference raising them off the grow room floor makes! Raise pots off the ground using wooden blocks or stands. This not only prevents cold transfer but also improves drainage and oxygen flow to the roots, keeping your soil and the soil food web as healthy as possible.

Check Your Nutrient Solution Temperature

Cannabis plants prefer a nutrient solution temperature of around 68°F. Using cold water can shock roots and slow growth, and cause plant growth to become stunted in some cases. Use a digital thermometer to check the water temperature before adjusting pH and EC levels, which can be purchased for a low cost at an aquarium store. 

This way, you can maintain a consistent nutrient temperature with your cannabis feeding schedule when growing with hydroponic systems. You won’t need to be concerned about shocking your roots.

Use Heating Mats for Seeds and Clones

When the house is cold, germination can be slow, prolonging the time it takes for clones to root. A simple solution to this problem is to purchase a small heating mat. The same type that can be used for reptiles. A heating mat or heat pad provides gentle warmth when germinating cannabis seeds and clones. Place heat mats in a propagation tent or converted cupboard to keep your seedlings cozy and your roots strong from the start.

Add a Heater In The Same Room As the Tent

A small heater in your tent or grow room can make a huge difference. Use it only when the lights are off to keep nighttime temperatures between 64°F and 68°F. Select a low-wattage heater that operates safely during dark periods without consuming excessive power. 

Alternatively, you can place a gas heater in the same room as your grow tent at night to help maintain optimal temperatures. If the drop in light on and light off temperatures exceeds 8 degrees, this can cause plants to stretch and become lanky, which can seriously affect yields.

Good luck keeping your grow room cozy and warm, and not needing to worry about cold and humid conditions!

Feature Photo: This flowering remains between 64°F and 68°F when the lights are off. Photo credit: Stoney Tark