Heat Management When Growing Cannabis

If you are planning on growing your own cannabis at home, one of the most important things that you need to do is consider the temperature.

Heat management is a very important factor to keep in mind for cannabis plants. If cannabis plants are growing in temperatures that are either too hot or too cold, it can spell disaster for your crop. Therefore, today we are going to discuss what the proper heat management techniques are for growing cannabis.

We’ll talk about what the ideal temperature range is for each growth stage, how to control the temperature, and what happens if your weed plants are growing in temperatures that are either too hot or too cold.

Ideal Temperature for Cannabis

Whether you are growing indoors, outdoors, or inside of a grow tent, temperature management is crucial to be considered. What many people don’t realize is that cannabis plants require different temperatures throughout each of their three main growth stages. This includes the seedling stage, the vegetative stage, and the flowering stage. Some people may also consider the harvest preparation stage a fourth stage, although this is questionable.

Seedling Stage

During the seedling stage, the ideal temperature for cannabis plants is between 70 and 80 degrees Fahrenheit, or between 21 and 27 degrees Celsius. This is during the day, although during the night, the temperatures should be significantly cooler, between 65 and 75 degrees Fahrenheit, or roughly 18 to 24 degrees Celsius.

Having the temperature be fairly warm during the germination and seedling stage will encourage healthy and fast growth, whereas cooler temperatures may slow down the growth of the seedling and increase the risk of disease. To maintain the optimal temperature for cannabis seedlings, many people use a heat mat. A heat mat, or even something as simple as an aquarium heater can go a long way in maintaining the right temperature for those seedlings.

Vegetative Stage

During the meditative state of growth, the ideal temperature is between 70 degrees and 85 degrees Fahrenheit, or roughly 21 to 29 degrees Celsius during the day.

During the night, the temperature should be between 60 degrees and 70 degrees Fahrenheit, or between 15 and 21 degrees Celsius. This is extremely important because the maintenance of proper temperatures will allow for fast vegetative growth, the development of strong leaves and branches, and healthy root growth.

Flowering Stage

During the flowering stage, particularly the early flowering stage, the temperature should be between 65 and 80 degrees Fahrenheit, or between 18 and 27 degrees Celsius during the day, and between 60 degrees and 70 degrees Fahrenheit, or between 15 and 21 degrees Celsius at night.

During the late flowering stage, however, cannabis plants should be kept slightly cooler, between 65 and 75 degrees Fahrenheit or 18 and 24 degrees Celsius during the day and between 55 to 65 degrees Fahrenheit or between 13 and 18 degrees Celsius during the night.

What is important to note is that when cannabis is in the flowering stage, temperature fluctuations can negatively impact resin production and bud development. Towards the end of the flowering stage, slightly cooler temperatures may enhance the production of trichomes.

Harvest Preparation

When you are preparing for harvesting cannabis, the temperatures for the last two weeks should be kept at a consistent level, between 65 and 75 degrees Fahrenheit during the day, or between 55 and 65 degrees Fahrenheit during the night.

Why is the Right Temperature Important for Cannabis Growth?

The proper temperature for cannabis growth is indeed extremely important, and this is true for a variety of reasons. Cannabis can suffer if the temperature is either too low or too hot, so let’s take a look at some of the main issues here.

What Happens if Temperature Drops?

There are a number of issues that can occur if the temperature is too low for your cannabis plants.

• Cold temperatures will slow down the metabolic processes of your cannabis plant, therefore reducing the overall growth rate, with the ultimate result being a smaller size.
• Cooler temperatures may also lead to issues with the development of the root system, particularly when it comes to being able to absorb water and nutrients, ultimately leading to nutrient deficiencies.
• Cold temperatures may also cause the leaves of the plant to go yellow and may also cause chlorophyll to breakdown, which reduces the ability of the plant to perform photosynthesis, therefore hindering its growth.
• If the temperature is too cold for your cannabis plants, it can also cause an increased susceptibility to diseases as the immune system is weakened.
• If the temperature is too cold during the flowering stage, it may also cause a decrease in bud size and resin production. Check out our guide on 12 tips to maximize cannabis bud size.

What If Plants Are Growing in Hot Air?

The issues that occur when cannabis plants are grown in temperatures that are too hot are quite similar to the issues that occur when cannabis plants are grown in temperatures that are too cool, so let’s take a quick look at what the biggest issues might be.

• One of the biggest issues that occurs when cannabis plants are grown in temperatures that are too hot is that photosynthesis will be reduced, ultimately slowing down the growth and development of the plant.
• If temperatures are too hot, water may evaporate from the plant faster than the cannabis plant can take in water. This can lead to water stress, drooping leaves, wilting, and more.
• High temperatures may also disrupt the uptake of essential nutrients by the root system of your plant, therefore slowing down its growth.
• Ultimately, high temperatures can lead to heat shock and heat stress, which is characterized by the damage of plant tissue, which can ultimately lead to the death of the plant.
• If the temperatures are too high, diseases and pests may take hold more easily.
• Excessive temperatures may also lead to the disruption of bud development, ultimately leading to lower yields and lower potencies of the buds.

How to Manage Grow Tent Heat

Now that we know what the optimal temperature for your cannabis plants is, and what can happen if the temperature is either too high or too low, let’s take a look at some of the best methods to manage the temperature in your grow tent.

Air Circulation is Key

Keeping a grow room warm is important, but this also means that you need to pay attention to air circulation. To maintain the optimum temperature in the grow space, having good air flow is important.

The faster the air is flowing, generally speaking, the lower the temperature will be, and if there is no air flow, it generally allows for a buildup of temperature and humidity. Therefore, you want to create a bit of air flow using something like a regular air fan to control the air circulation and temperature in your growing environment.

It also helps if you have a unit where you can control the fan speed, because this will allow you to control the temperature and air circulation in the entire tent. Having a unit with a good fan speed controller is therefore recommended.

Get a Good Ventilation System

If you have an indoor growth space, one of the best things you can do to control the temperature is to allow for proper ventilation inside of the grow tent. To maintain the optimum temperature, you can always try using something like an air intake.

An air intake, combined with a good exhaust fan, will allow you to adequately control the temperature inside of the growth space, as well as humidity levels.

Cycling air between the outside and the inside of the entire tent will help manage temperature and humidity levels better than most other things.

At the very least, having some good air vents can provide you with the circulation and ventilation your plants need, which ultimately helps to maintain the perfect temperature. Furthermore, this will also allow your plants to get some fresh air, which is very important when you have an indoor garden. An indoor garden has a hard time getting fresh air, but that oxygen is crucial for plant growth.

Manage LED Lights and Other Heat Emitting Equipment

Although LED lights and other such units are very important for your plants growth, remember that they also produce a lot of heat. Any extra light your fixtures produce translates into extra heat, which can especially be the case with something like HID lights.

Of course, this issue is not as big if you are growing outside in direct sunlight, but nonetheless, sources of light also produce heat. Therefore, you want to ensure that you have a high quality LED light that comes with a heat dissipation system. This will allow you to keep the room cool and at the right temperature for your cannabis plants.

Monitor the Temperature

Remember that both excessively high and excessively low temperatures can negatively affect the health of your cannabis plants. It can even go so far as to rendering your nutrient solutions useless, because your cannabis plants can no longer take up those nutrients properly.

Therefore, get yourself a good thermometer that allows you to accurately measure the temperature in the grow space. When growing plants indoors, monitoring the temperature is extremely important period you need to be able to control the temperature very accurately if you plan on being successful in your cannabis growth journey.

Use Insulation to Prevent Temperature Fluctuations

To prevent temperature fluctuations from occurring, so you can prevent excessive cool air and excessive warm air from causing temperature shift, using a well insulated space is important period many grow tents come with insulation for this purpose.

This will allow you to maintain constant ambient temperatures, because remember, temperature fluctuations can be extremely negative for your plants. You don’t want excess heat or cooler air fluctuating with each other, because this can cause some huge problems.

Use Ideal Watering Practices

To control the temperature inside your grow tent, it’s also important to use ideal watering practices. Remember that if you over water your plants, the air may also become saturated with excessive humidity, which can also affect ambient temperatures.

Make sure to provide your plants with enough water so they can survive, but not so much that it can change the temperature. Remember, the watering schedule will also affect soil temperature, which can make a difference.

Use Heaters and Coolers

Finally, if you want to control the temperature inside of your grow room, there are plenty of tools that you can use. Air conditioners are one of these tools. An air conditioner is perhaps the easiest way to keep the temperature at the ideal level. You could use either central air conditioning, a portable air conditioner, or even a wall-mounted air conditioner. They will all do just fine.

However, it may also be the case that the grow room is a bit too cool, in which case electric heaters come in very handy. Having a tent heater set at the optimal temperature will allow the cannabis plants to thrive without you having to do any work. There are also simple tube heaters out there that allow you to maintain slightly higher temperatures if necessary.