Indoor horticulture is a simple, yet complicated hobby. For the most part, the basics of outdoor gardening apply to gardening indoors. Light, water, nutrients, and atmospheric conditions are all major contributing factors to how well an indoor garden performs.
However, indoor horticulture is unique because it provides a heightened level of control. Still, that heightened level of control comes with additional steps that are needed to make an indoor garden live up to its potential.
The more a person grows indoors, the more he or she discovers the seemingly insignificant things that can have a dramatic impact on growth and yield. Two examples are keeping your garden light tight and under slight negative pressure.
Slight Negative Pressure in a Grow Room
Security is an important aspect of indoor horticulture that many novice growers overlook until it is too late. After all, many indoor gardens contain expensive equipment and valuable crops that can attract unwanted attention.
Fertilizers and plant odor are particularly certain to grab the attention of anyone in the vicinity. Various devices can be used to eliminate or cover these odors, but a grower can still run into issues if he or she does not have a proper ventilation set-up. The first step to eliminating odor emitting from a garden is to ensure the garden space has a slight negative pressure.
Negative Pressure vs. Positive Pressure
In most cases, an indoor garden’s negative or positive pressure is determined by the ventilation system. If the garden space is exhausting air faster than it is pulling in fresh air, the garden room will have a negative pressure.
If the garden space is bringing in air at a faster rate than it is being exhausted, the garden space will have a positive pressure. Gardeners who use grow tents can easily observe the difference between positive and negative pressure.
When the walls of the grow tent are bowed outward, the air is entering the tent faster than it is being exhausted (positive pressure). When the walls of the tent are drawn inward, the air is being exhausted faster than it is entering the tent (negative pressure).
As previously mentioned, the key to odor control in an indoor garden is to have a slight negative pressure. With a slight negative pressure, the air within the garden space is contained (except for the air being actively exhausted).
The negative pressure will also keep all the odor contained within the garden space. This means a grower can set up a device, such as a carbon filter, to remove the odor as it purposely exits the garden space.
When positive pressure is present, the odor is not contained in the garden and can be pushed out of any crack, crevice, or pinhole before it has a chance to be treated properly. Simply put, the odor will leak from the garden.
Some growers use a carbon filter or other devices in a recirculating manner to control odor. For example, a fan combined with a carbon filter will actively recirculate and remove odor from the air within a growroom. However, even when this is implemented, a negative pressure is the only way to ensure all the odor is contained and/or treated before exiting the growing area.