Quest representative John Pratt answers 6 of the most pressing questions about dehumidifier placement.

The location of a dehumidifier in your grow room can make or break its efficacy and efficiency, says Quest Dehumidifiers representative John Pratt. Concentrating your dehumidifiers in one corner of your room will create humidity pockets and could cause them to “fight” each other, Pratt continues, which not only is inefficient but could also hurt your units’ longevity. “You don’t want to try to remove moisture from air that has just had moisture removed from it,” he explains.

Here, Pratt answers common questions about dehumidifier placement to optimize both its efficiency rate and how you can use your dehumidifiers to increase airflow.

1. How does the location of my dehumidifier in my grow room affect my environment?

Having a dehumidifier in the right place in a grow space can help a grow environment tremendously. Adversely, a dehumidifier in the wrong place can result in little to no effect. In the wrong position, a dehumidifier can struggle because of things like cold air from an AC, poor spacing of dehumidifiers, not enough room from the wall, too far from the plants (if the room is very tall).

2. What is the optimal location to reduce humidity?

This depends on how many dehumidifiers you need. If only one is needed, centrally located in the room, above or next to the lights is generally the best placement. There are variables that affect placement, such as room height and airflow. For example, when a room has a low ceiling you might not be able to hang your dehumidifier. In this case, we might recommend a floor placement or under a table. We recommend reaching out to us or a licensed HVAC professional to ensure correct placement.

3. What is the optimal location to increase airflow?

Place your dehumidifier at the recommended distance away from the wall to eliminate “choking” of the machine. Also, placing it away from direct flow from an air conditioner or heater will help with airflow.

Each dehumidifier has different wall spacing guidelines. Make sure to reference the owner’s manual if you plan to place near a wall. For example, Quest’s 5 Series dehumidifiers should be a foot from the wall.

4. What advantages do different potential locations offer?

There are multiple options for placement. The decision comes down to the grower in each individual space. Every grow room is slightly different.

Some growers prefer to have them under their tables. This is perfectly fine. They will perform well as long as there are no obstructions to the supply and return openings.

Some growers do not have the room to hang their dehumidifiers in the middle of a room and put them at the end instead. This is also fine as long as they are not near the AC and not restricted.

Lastly, there are growers that simply do not have any space for more equipment and duct their dehumidifier from outside the room. This is a great solution for people who have limited space. The only thing to avoid is running the duct too long. You want to keep the duct length under 30 feet.

5. If multiple units are required in one room, how should growers space them out to maximize efficiency?

The best way to place multiple units is to space them out evenly throughout the room. This eliminates the possibility of humid pockets.

6. How many fans should cultivators add to maximize airflow and dehumidifier efficiency?

A: This is grower preference, but we recommend as many as you can without damaging the plants. More airflow the better is our recommendation; just not at the cost of the health of the plant. You want to see plants “dancing” from the airflow but you don’t want to see severe bending of the entire stalk.

Editor’s note: This Q&A has been edited for length and clarity.

Photo at top: A grow room with two Quest dehumidifiers. This company was forced to put two units next to each other, but added more fans to increase airflow and reduce the risk of humidity pockets.

Equip yourself with the right tools to increase yields and avoid pest problems.

Determining your dehumidification needs as a cultivator can be one of the toughest tasks you must accomplish (ideally) before plants are placed in the grow rooms. There are so many variables to consider: the number of plants you plan to have in a room, the amount of water you are giving your crop, your growing method, and the size of the room must all be factored into your calculation, says John Pratt, a representative from Quest Dehumidifiers. Add to that determining available voltage, power allotment, and the physical space available for the equipment and what seemed like a simple dehumidifier purchase has turned into a jumble of data points and calculations.

Improper humidity levels can be hard to diagnose and costly to fix if you have the misfortune of losing a crop. Telltale signs of humidity issues growers are familiar with are powdery mildew and bud rot, but Pratt says a simple drop in production can also be a warning sign as “decreased yields are also an indicator of poor plant health.” He adds cultivators can know they are on the right path when yields are high and consistent. “Growers who have mastered their environment tend to have bigger, healthier plants,” he says.

To help growers with their dehumidification calculations, Quest offers a sizing calculator on its website, which will “assess the amount of dehumidification needed and then recommends the best size dehumidifier and the quantity needed,” Pratt explains. The calculator takes into account your daily water feedings, your energy cost per kilowatt hour and how many weeks per year cultivators grow. For example, in a room that receives 50 gallons of water per day, 52 weeks per year at an energy rate of $0.20/kWh, the calculator recommends cultivators use three Quest Dual 155 units, and compares the Quest units with other competitor products in the market.

There are other ways for cultivators to determine their dehumidification needs, including through the use of hygrometers and data loggers to measure humidity levels over a set period of time. However, if cultivators use a vertical farming system, “there is going to be a much higher need for dehumidification,” Pratt says. “Also, if the rows are very long, you might need to spread out your dehumidifiers along the row to get even dispersion.”

Seeing as how no two cultivation businesses are set up exactly the same, Pratt says the best way for cultivators to get an accurate reading of their humidification needs “is for our experts to visit growers and help them on an individual basis.”

Photo at top: A Quest 506 dehumidification unit. While most rooms will only require one dehumidifier, cultivators using vertical farming systems should account for increased humidity.

The WSLCB says relabeling physical inventory is not required.

The Washington State Liquor and Cannabis Board (WSLCB) wants retail licensees to know they can accept product from producer/processors when the manifest has new Leaf Global ID numbers. The new Leaf Global ID numbers on manifests will link to Contingency ID numbers or old traceability ID numbers from the legacy system used prior to the Contingency period, according to a press release.

Some individuals/businesses have encountered an unforeseen struggle while attempting to cut over their current plants and current inventory into the new Leaf traceability system.

Licensees have raised concern about products not being physically labeled with the new Leaf ID numbers.

When product is electronically entered into the Leaf system, it will have the old contingency number, or possibly even the legacy system identification number physically on it. We do not expect licensees to relabel all of their product/plants with new numbers. Instead, it is expected that new numbers are physically attached as soon as actions such as conversions, harvest or lotting are made.

Licensees may transfer and receive product with the contingency or historic numbers still physically attached to the product. For example, retailers do not need to physically relabel their inventory, and processors sending  packaged end product to retailers do not need to physically relabel all their product prior to sending it.

It is expected that the historic IDs are linked to the new Leaf IDs by the third party software system or licensee entering the Contingency ID or old traceability ID into the “Contingency/Old Traceability” field into Leaf Data Systems when inventory is uploaded.

Because this only applies to product that is being uploaded as initial Leaf inventory, this exception will only apply to those items that existed prior to implementation of Leaf Data Systems.

His fight with Jeff Sessions has put the future of 11 Justice candidates into limbo—and more are in the pipeline.

WASHINGTON — It’s been a month since the marijuana blockade began, and U.S. Sen. Cory Gardner is standing firm in his vow to jam all appointments to the Department of Justice until Attorney General Jeff Sessions softens his stance on marijuana.

So far, his siege to protect both Colorado’s cannabis industry and the state’s sovereignty has prevented as many as 11 nominees from getting a Senate floor vote—the last major step before they can start work—and there is little indication that Gardner, R-Colo., and Sessions are any closer to finding common ground.

“It may never resolve itself,” said U.S. Sen. Chuck Grassley, R-Iowa, who chairs the committee in charge of getting these nominees to the floor.

If that happens, the consequences would extend far beyond the 11 nominees that Gardner has put on ice.

More than 20 other candidates are in the congressional pipeline for Justice-related jobs, including U.S. marshals and U.S. attorneys assigned to states across the country. One even hails from Colorado: David Weaver, a former Douglas County sheriff in line to become the state’s next U.S. marshal.

The move to legalize adult-use cannabis is gaining some traction in the state capitol, but the lawmaker behind it admits it won't be easy.

ATLANTA - The move to legalize recreational marijuana is gaining some traction in the state capitol, but the lawmaker behind it admits it won't be easy.

Given the fact that Georgia has a GOP-controlled legislature and it’s an election year, Channel 2 political reporter Richard Elliot learned the chances the state will legalize recreational marijuana is slim, but the bill’s sponsor told Elliot that support is growing.

“The historical trends and the political trends nationally, and even here in Georgia, are on our side,” state senator Curt Thompson, D-Tucker, said. 

Thompson said he knows he’s fighting an uphill battle, but, once again, he’s introduced a measure that could legalize recreational marijuana.

Top image: © Andy Dean | Adobe Stock

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