The world is a big place, and growers live in lots of different climates. It can be very hard sometimes to keep the space where your plants grow consistent, and this inconsistency can be detrimental to your plants’ development.
So how do you get that environment in your grow space under control?
Farming is one of the most ancient skills of humanity, and even though there are still lots of things we’re learning, there are actually several tricks and tips that you can use.
Are Your Yields Being Limited?
There once a person named Carl Sprengel who made a very poignant observation in the 1840s. This other guy named Justus vo Liebig had a better name and publicist, though, so when Justus took Carl’s idea and spread it around, it became known as Liebig’s law of the minimum.
Basically, Liebig’s law states that growth is not dictated by the most abundant resource, nor even the sum of all resources, but by the most scarce.
Think about a barrel. If you have a barrel with all the staves the same size, when you fill the barrel with water, the water can be filled all the way to the top of the staves. If the staves are of different sizes, however, the water can only fill up as high as the shortest stave, where it will start pouring over.
When looking at your grow space, it’s important to keep everything in mind. When considering the environment, this includes:
- Relative Humidity
- Air quality
- Air flow
Technology Can Help
To keep all these in balance, there are several pieces of equipment that serve the grower’s efforts.
A very helpful item that our gurus suggest getting straight away and keeping around for every grow and every space is a hygrometer.
A hygrometer takes readings of temperature and relative humidity, allowing you to get an understanding of your environment even before you set up your space. Knowing what you are getting into before you begin is the best way to avoid problems down the road.
Once you have a basic understanding of the issues you will be facing, and once you have chosen your space to grow, you can approach growing already prepared to deal with environmental issues.
Controlling Grow Room Temperature
Every plant will grow best when subjected to temperatures like those found in its natural environment. For most garden plants, the golden window of healthy growth is between 65 and 85 degrees Fahrenheit, or 18 to 29 degrees Celsius.
If you are growing indoors in the same space you’re living, It’s a good rule that if you’re comfortable with the temperature, your plants are comfortable. Many homes are equipped with air conditioning and heating to solve this problem, and when it comes to your grow space, the same equipment can be utilized.
Keeping portable heaters and air conditioners in your grow space is a possibility. There are also several systems designed specifically for controlling temperature in grow environments.
If you are growing in a grow tent, companies like AC Infinity build temperature control systems that filter air in and out of your tent while monitoring and controlling the temperature in the tent. Since lights inside are “warm” and the plants are “humid” this is the simplest form of environment control.
If you are growing in a closet, basement, or other area inside your home, a minisplit a/c unit is a favorite tool of many. It utilizes a compressor housed outside the building, running a refrigerant line to the indoor air conditioner.
It’s also good to consider the day/night cycle of your plants. During the night cycle, it is recommended your grow space be 10 degrees (Fahrenheit) cooler than during day cycle. A thermometer will help monitor this, and many air conditioners and heaters alike are equipped with built in thermometers that switch the unit off if the temperature is within optimal range.
There are, of course, bigger equipment issues to consider that contribute to temperature control in your grow space. HID lights give off an immense quantity of heat, making control of the environment, especially in small grows, very difficult. LED fixtures mitigate this problem very handily.
Our Electric Sky LEDs work for your plants best when the temperature is in the low 80s and the relative humidity is 55-65%.
How Can I Keep the Humidity in Check?
The relative humidity of your garden can be pretty hard to keep consistently under control, especially when living somewhere very wet or very dry. Your hygrometer will tell you the relative humidity of the environment, but it should also be noted that your plants themselves will add to the relative humidity.
Relative humidity will change from day to day, and throughout each day. Your hygrometer will let you know where it’s at. Regulation of humidity is best done with humidifiers and dehumidifiers. Remember that your plants themselves will affect your humidity levels, and when leaves are too layered together, you risk mold.
You may likely find yourself running both a humidifier and a dehumidifier at the same time, which seems counterintuitive, but when you are living in an environment of widely differing humidity, it is best to keep control of your space.
If a humidifier/dehumidifier isn’t available to you, running an exhaust fan to draw out the humid air will serve you well.
You may also want to consult a Vapor Pressure Deficit (VPD) chart to find your optimal humidity. VPD charts give the plant focused relative humidity best suited for any particular temperature. It is helpful to know where your humidity should be as you watch your temperature throughout the day.
The Importance of the Flow
You’ll want to keep your air flowing throughout the space all the time. The benefits of constant air flow include:
- Reduced risk of mold
- Building stronger stems and leaves
- Cooler ambient temperatures
- Maintaining air quality
If you are growing inside your home, the room that houses your grow space is called your “lung room”, because it’s the room that decides what sort of air your plants will get. You can run your exhaust into your lung room, but if you do, you’ll probably want to monitor the air quality and temperature of that room. Running exhaust outside, to an attic or to another unattached part of your home will ensure you are always adding fresh air to your garden.
It’s best to keep a steady amount of airflow moving through your space. If you see all your leaves gently moving, you’re doing great.
When working out your air flow, there are a couple important things to keep in mind. First, it’s a good idea to have all of your exhaust running outside, or at least to an attic or somewhere away from any ambient areas. Last, keep an eye on the amount of air moving through your space. A little bit of wind is good, but too much can damage your plants.
For optimal air flow, we recommend having your air input down low, near the floor, and your outtake up high. The idea is to get air flowing through the whole plant, not just across the canopy. Adding a fan about mid-height would be very helpful as well.
A passive intake system utilizes an extraction fan to pull air out, drawing air in naturally. An active intake system uses a fan to push air into the grow space. Whichever way you choose, make sure you are moving air in and out evenly, so you’re not filling your space with extra pressure, but your not suffocating your plants either.
Air flow can help control the quality of air as well. During the day, plants intake CO2 and expel oxygen, while at night, the process is reversed. CO2 can become a little scarce in a grow room, where the plants are pumping out oxygen and eating up all the CO2 all day. Just think about yourself sitting in a small room for an extended period; how stale the air becomes after a time.
While this problem can be very acutely attended by adding CO2 pumps into your grow space, this option is costly and is only viable in a closed-loop system where no outside atmosphere is getting into your plant space. Just keeping your air flowing will rejuvenate the air quality perfectly fine.
A carbon filter is a great thing to add to your air extraction system. I not only cleans the air of any imbalances in the air, but traps the carbon particles that carry odors from your plants, so your expelled air in fresh and clean.
What’s Most Important?
While there are many different things to consider when dealing with your environment, a simple home grow can be very successful with just a few foundational measures.
- The purchase of a hygrometer is definitely suggested, as it will help you see what you must do to keep things in check.
- Fans to keep the air moving will be of great service to you in producing healthy plants, and if your space can accommodate it, an intake/outtake ducting system will be very good as well. Remember to run your exhaust out and away from any ambient areas, and put a carbon filter in there as well.
- Humidifiers and dehumidifiers are helpful in keeping your plants stable. You don’t want the leaves and flowers drying out, nor do you want to see mold and fungus growing where it isn’t welcome.
- An air conditioner and/or heater may be of use if the room is especially susceptible to temperature swings, but if you’re growing in your home, the temperature controls you use to keep your living space comfortable will suffice.
Remember, there will be a significant difference in environmental needs when growing in a closet or tent in your home versus growing in an exposed garage, basement, or shed. When growing in your home, the room that houses your grow space is called your lung room. If it’s comfortable for you, it’s probably comfortable for your plants.
Moving out of a tent in your room to a garage or other more exposed space, be prepared to spend more money. The more elaborate or bigger your grow space, the more effort it will take to control that environment, and the more exposed it will be to the natural elements. Growing in more vulnerable spaces will require more equipment.
Wherever you are growing, There are many great ways to keep the environment around your plants in prime order. We hope this basic guide is helpful to you. Remember, you can always post questions in the comments and we will answer. Happy growing!