Best Climate for a Cannabis Grow Room

Cold-Air Dumping

Researchers have discovered that most temperature-related stem elongation occurs during the first few daylight hours. It is possible to yield short and compact plants with short internodal gaps by keeping the temperature lower than the nighttime average during the first two lights-on hours. Use a timer and a portable AC unit to create a cold-air dumping effect.

What to Do When Temperatures are Too Low

If the grow room’s temperature drops below 15°C or 60°F, the plants’ metabolism will slow, and growth will stop. At or below 4°C or 40°F, tissue damage will occur, and it may not be repairable. If this occurs during the flowering stage, the plants might not mature properly. Generally, with the use of HID lamps, daytime temperatures will remain at an appropriate level. During the night, or if you are using LEDs, the room may get cold. We have already explained what happens to cannabis plants if they get too cold, but thankfully, the problem is easy to resolve. Follow these tips:

• Do not bring air in from the outside during winter.
• Keep pots off the floor to fight low root temps.
• Minimize exhaust fan usage. With a speed controller or timer, you can ensure that the fan works for air exchange, not heat extraction.
• Use a submersible heater to keep the nutrient solution warm.

Next, you will learn what to do if it gets too hot in the grow room.

Preventing Mildew

To prevent the growth of mildew and mold, cannabis must be grown in a very well-ventilated space. Most successful growers use fans to decrease temperatures and provide their plants with the air circulation they need.

However, it is just as important to remove hot air from the room. Ventilation cuts heat and controls humidity, which prevents plant stress and reduces the risk of disease. Providing ventilation may be as simple as cutting an opening into a cabinet or closet door. If you cannot make cuts, though, try leaving the door slightly open or using an outward-facing fan that is directed toward the ceiling. Some growers use carbon filtration and ducting to minimize scent and control airflow.

Odor Control

Many refer to marijuana as “skunk weed,” and for good reason. The plant has a very noticeable odor, particularly during its flowering stage. Though a good exhaust system will take care of the smell, that’s not the end of the problem.

To really get rid of the smell use a carbon filter. These filters are typically put inside exhaust fans so the air leaving the grow room is clean. The carbon inside the filter sucks up the scent of cannabis as the air passes over it. Cotton will help the filter last longer: wrap it around the filter cylinder to trap additional dust particles. Even with this step, you should still replace the filter media every six months or so.

The Dos and Don’ts of Grow Room Climate Control

Now that you are running a fully functional, professional grade grow room, it is time to focus on your next steps. From this point on, maintaining proper climate and humidity will help you maximize crop yield and profit potential. We have put together a list of dos and don’ts to help you achieve crop success.

• Do: use equipment that is customized to your needs. For maximum output, it is best to use custom-built equipment. Many growers believe that home dehumidifiers will work, but that is simply not the case. These units were not made to work at the low temps required for cannabis maturation.

Furthermore, cannabis plants add about eight pounds of moisture to the air every day. If you are growing a sizable crop, that is a lot of water (and a home dehumidifier simply will not cut it.) Get the custom gear you need, and you are more likely to succeed.

• Do balance the environment. It is crucial to maintain a balanced grow room environment, so bud rot and mildew do not damage your crops. The goal is to balance the crop’s health, the room’s airflow, and the light needed to illuminate the space.
• Do measure twice and cut once. It is crucial to double-check your work before deciding. Knowing your grow’s specs and defining your goals will help you maximize yield and profit potential.

And now, a few don’ts:

• Do not waste too much energy on portable equipment. As mentioned before, portable, home-use equipment will not work in a cannabis grow room. These units are typically inefficient, and they must work harder to do half the job done by a custom-made dehumidifier. When you are wasting energy, you are cutting into the bottom line.
• Do not permit temperature fluctuations. Cannabis is sensitive to changes in humidity and temperature, which will affect your yield. Referencing the need for balance, you will need to exert significant control over the indoor growing environment. It is a good idea to log indoor conditions every day, throughout the day, to protect your investment.
• Do not get impatient. Let your crops mature before harvesting them. After all, you have spent a few months tending to the crop, and you want to maximize your time investment and your yield. There are a few ways for even novice growers to tell when it is time to harvest the crop. The easiest way is to look at the pistils covering the buds. As flowering begins, they are stringy and white; when that period ends, they begin to turn brown or dark red. Though these color changes signify bud maturation, time frames and actual colors may vary from one cannabis strain to another. It can be very tempting to harvest your buds as quickly as possible, but it is crucial to wait until they are mature. If you have followed our tips this long, why not wait a few more days? With patience and perseverance, you will reap the reward of a full, lush, and fragrant crop from your authentic American cannabis seeds.

In Conclusion

Growing cannabis is simpler than it seems, but there are still many factors to consider when growing it indoors. By following the tips and guidelines provided in this article and others, you can control the climate inside your grow room and produce quality pot plants from seed. If you have not found seeds yet, please visit weed-seeds.com to begin your collection. Expert growers from Massachusetts to Connecticut boast about our premium seeds. Happy gardening!