When the East Coast Cultivation team started building their new indoor grow facility in Rhode Island, they knew they had to hit one thing: environmental controls.
“The key to successful growth is taking control of your environment,” said Joe Welch, CEO and co-founder of East Coast Cultivation. “As soon as you lose control of your surroundings, the serious shredding problems begin to take hold.”
The two main crop crushers are concerns that many growers face at one time or another: powdery mildew and botrytis, better known as bud rot. Each of these problems can destroy a growth and result in lost revenue of thousands.
Knowing this, Joe Welch and his team, including COO and co-owner Susan Welch, invested a lot of time dialing in their dehumidifier setup for the grow room. That setup, along with an HVAC system, forms the backbone of a well-controlled environment, Welch said.
To optimize a setup, growers need to focus on three things with their dehumidifiers, said Coleman Retzlaff, a factory representative at Quest, which provides commercial units to hundreds of cannabis growers nationwide: proper sizing, placement, and airflow.
Strength in numbers
“Water in equals water out” is the mantra for growers trying to enter their humidity. It may sound simple, but in practice it is a little more complicated.
Plants release almost all of the water they ingest into the air. In a sealed growing room, cultivators must take this water into account and remove it from the air to ensure adequate humidity. For example, if a grower consumes 25 gallons of water a day and 5 gallons go down the drain, that grower has 20 gallons left. There are eight pints per gallon (dehumidifiers are measured in pints per day), so you need to be able to remove about 160 pints from the air per day.
“When we do this calculation, it’s really that simple,” said Retzlaff.
A common misconception that results in a dehumidifier becoming too small in a grow room is the idea that air conditioning doesn’t require additional humidity control. While air conditioners can remove some moisture, they are designed to cool down, not remove water, and therefore not keep up with the demands of a growing environment.
In addition, air conditioners rarely run at night when the lights are off and no additional heat is added to the room. These are exactly the conditions under which mold and mildew can set in. At East Coast Cultivation, Welch and his colleagues found it better to oversize their dehumidifier configuration with devices that they can use to prepare for possible worst-case scenarios.
“The best tip for entering your humidity is the right size of your equipment and dehumidifiers that use automated controls,” Welch said.
He’s in good company with this council. Seth Lee, an experienced grower in Colorado, has calculated how much water his flower room is using when plants are giving off most of the water. He operates six dehumidifiers, each of which can draw 225 liters of water from the air every day. Lee admits his flower room may feel a little overworked – but he’d rather be safe than embarrassed.
“If you don’t invest in proper environmental controls, it’s almost negligent,” said Lee. “You are preparing for failure because humidity control is an integral part of an integrated pest control strategy and I include powdery mildew and fungus as pests.”
Regardless of whether a grower is running a single dehumidifier or a legion of ten, proper placement is key to its effectiveness. Knowing how to place dehumidifiers helps maintain a stable environment and reduces the risk of creating microclimates where moisture spikes and mold can occur.
To ensure proper placement, Lee advises growers to keep each dehumidifier evenly spaced. It is also important that producers pay attention to details such as: B. Point the filter side toward the center of the room and periodically check that each unit is draining properly.
“We run dehumidifiers over the lights to save space and rely on good airflow from the fans to evenly mix the air,” Lee said.
According to Retzlaff, as the size of the growing areas increases, the distance has become increasingly important, as it enables the humidity to be controlled in zones. For example, instead of running 15 dehumidifiers at the same time and then turning them all off, each one is automated to independently detect when the humidity increases in its zone. This approach keeps the room’s relative humidity more stable and increases energy efficiency, he said.
At East Coast Cultivation, lead breeders and co-founders Alex Welch and Tyler Greenless took a modular approach where the dehumidifiers were spaced so that if one needed servicing, the others could maintain proper humidity levels in their absence. “You need to add redundancy,” said Greenless. “We would rather have three units that each draw 225 pints than one that draws 700 pints. If that 700 pint unit fails, you have no backup, and if it’s not serviced quickly, you risk a moisture surge and mold growth. “
Pay attention to the airflow
Finally, understanding the shape of each room and the way air flows and mixes in that room is critical to ensuring that any dehumidifier setup will maintain a consistent level of humidity in a growing room.
In a long room, producers need dehumidifiers that are evenly spaced to create a circular flow of air. If the room is narrow and a dehumidifier is available, according to Retzlaff, the discharged air can be pushed over the room to get an even mixture of air over the plant canopy. This is a stark contrast to a high room where producers may want to direct the return air to the floor for an even flow of air.
“We can direct our dehumidifiers from the flow and return openings into the direct air, where the producers want it and how it works best for their environment,” said Retzlaff. “That added bonus can play a big role in establishing a constant humidity level.”