How to Make the Best Growing Environment

by Nebula Haze

What makes the perfect cannabis growing environment? What does it take to get the healthiest growth and best yields from your indoor cannabis plants?

Consider a grow tent if you want a pre-made perfect growing environment for your marijuana plants!

5 Factors to Creating a Perfect Growing Environment
(from most important to least important)

  1. Light – Bright but not too bright
  2. Temperature – Comfortable for you, comfortable for your plants
  3. Air Circulation – Fresh air plus a gentle breeze
  4. Reflection – Cover your walls with a reflective material
  5. Humidity – Controlling humidity helps plants grow faster and can increase resin production

You need a great environment to produce the best harvest. A poor growing environment lowers both yields and bud quality!

Platinum color cannabis nug from jar - proper marijuana growing techniques is what it takes to grow top-shelf bud like this!

Benefits of a great grow environment

  • Plants grow faster
  • Harvest bigger yields
  • Healthier, greener, and overall hardier plants
  • Higher bud quality (better bud density, shape, and trichome production)
  • Stronger bud smell and potency (THC and smells can get “burned off” if it’s too hot)
  • Plants are more resistant to common problems like over/underwatering, hermies, heat stress, light stress, bugs, mildew and but rot

Keep plants comfortable and they will reward you!

Purple Girl Scout Cookies plant


1.) Light

When growing cannabis, you want to give light that is bright but not too bright. The amount of light you provide is one of the major factors that will determine your yields, and with smaller grow lights your yields will be limited no matter what you do.

Light also changes how your plant grows. For example, the color spectrum of light can cause your plants to grow tall and lanky or more bushy and squat. Some grow lights like LED grow lights take advantage of a custom color spectrum to help your plants grow as optimally as possible.

The amount of light you give your cannabis is the main factor that determines your yields

Example of flowering cannabis buds under a 600W HPS grow light

However, it’s also possible to give your cannabis plants too much light, especially with big grow lights, so it’s important to keep grow lights the right distance away.

Learn about different cannabis grow lights


2.) Temperature

The long and the short of it is: If it’s comfortable for you, it’s probably comfortable for your plants.

Cannabis plants like temperatures in the 65-85°F (19-30°C) range and can start to run into problems when the plants are experiencing temperatures outside that range.

Optimal Temps for Growing Cannabis

Optimal temperature for growing cannabis - Vegetative Stage is 70-85°F (20-30°C) - Flowering Stage is 65-80°F (18-26°C)

Learn more about cannabis plants & temperature

3.) Air Circulation & Exhaust

Making sure your plants always have a gentle breeze and plenty of fresh air helps them grow faster. Good air circulation also helps prevent problems with white powdery mildew, bud rot, and common cannabis pests like fungus gnats or spider mites.

Basically, you want a gentle breeze moving over, through, and under your plants if possible. If all the leaves are being gently rustled, it’s perfect. You don’t want to point a fan directly at your plants because that can cause wind burn, but you also don’t want any leaves sitting in stagnant or hot air. A small oscillating fan or two in the grow space can work wonders.

Growing cannabis circulation diagram

In addition to making sure there’s air moving around in the grow space, it’s also important to vent out heat from your grow lights, especially if it’s getting too hot for your plants during lights-on. While many growers know they’ll need ventilation with powerful HPS lights, it’s important to note that ventilation can be just as crucial for LEDs, LECs and even fluorescent lights like CFLs or T5s if the total wattage gets high enough. For each light type, the higher the wattage, the more heat produced. If you notice the temperature is climbing above 85°F (30°C) on a regular basis, you should consider venting heat out of the grow area to keep the temperature under control. However, if the overall temperature of the entire grow room is too high, you may need to take more drastic actions such as getting an AC. Fans can move air around, but can’t lower the total amount of heat in a room.

Read the air circulation & exhaust tutorial for detailed instructions.


4.) Reflection

You will get the most from your indoor grow lights by reflecting light at your plants. Instead of letting the walls of the grow space absorb extra light from your grow light, you can use a reflective material to bounce it back towards your plants. This allows you to squeeze more yields out of the same grow light without having to change anything else about your environment.

Flat white paint is an easy and effective reflection option for your cannabis grow room walls

Flat white paint spray - use on your cannabis grow room walls for increased reflectivity   

Flat white latex paint is a surprisingly cheap and easy wall material that has 85-95% light reflectivity. Yes, it’s true, simply painting your walls can actually increase your yields! There are also many other materials with great reflectivity, and some of the professional options work even better than paint.

Learn which materials are the most reflective 


5.) Humidity

Unless it’s very high or low, humidity usually won’t cause any major problems with your cannabis grow. However, there are a few tricks with humidity to get faster growth and more resin production on your buds.

Optimal cannabis humidity levels chart

Note: The optimal seedling humidity is closer to vegetative plants than clones. Try to avoid letting the humidity get over 60% for seedlings or it can slow their growth.

Learn how to use humidity to “trick” your plant into growing faster and creating more resin


Perfecting Your Growing Environment

It’s important to realize that there is no one “perfect” growing environment. Just like people, each plant is a little bit different and may respond better to some environments than others. For example, some plants can better handle the heat or cold, and some plants aren’t as picky about good air circulation. But by taking care of the 5 factors of a great cannabis growing environment, you will ensure that your plant will be comfortable no matter what the strain!

And of course, if you run into any problems, diagnose your sick cannabis plant right away!



Jump to…

How to Increase Bud Quality

How to Increase Yields

What Determines Your Yields?

How to Grow Better Smelling Buds




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