Using Climate Control to Enhance Cannabis Growth

Statehouse by statehouse, the legalization of marijuana is steadily making its way across the country. As a result, cannabis markets are springing up as entrepreneurs look to cash in on the end of state bans. The legal marijuana trade is relatively young, with grow facility owners and operators still learning the ins and outs of producing large quantities of cannabis crops.

One of the initial challenges discovered in grow house operations is the problem of humidity. Humidity is the measurement of water vapor in the air. Higher temperatures typically result in higher humidity since warm air has more space to hold water vapor molecules. To maximize cannabis cultivation, growers must adjust their houses for optimal humidity as well as vapor pressure deficit.

Vapor pressure deficit (VPD) reveals the difference between the vapor pressure inside a plant’s leaf and the vapor pressure of the air.^[1] Plants depend on the pressure differentiation to extract nutrients through their roots, transport minerals, and perform a variety of other biological processes.

A grower must carefully control their spaces for humidity and temperature in order to create an environment for plants to thrive. In the beginning stage of cannabis maturation, growers should target a VPD of 8.0-11, which translates to a temperature of 77° – 79°F and 65 – 75 percent humidity.

Within the third and fourth weeks, the plants will enter the flowering stage which requires them to uptake more nutrients, necessitating a VPD of 10-13.5. Lowering temperatures to 75° – 77°F with a humidity of 55 – 65 percent can achieve the desired VPD.

In weeks five through nine, the VPD should be between 13-15.5, requiring temperatures of 74° – 76°F and a relative humidity between 42 – 51 percent. The cooler temperatures and humidity reduction will facilitate better consistency of irrigation dry downs.

Carefully managing temperature and humidity can help cannabis growers yield robust quantities of higher quality marijuana plants. It’s essential to size a grow house’s cooling system so that it exceeds the heat delta that gardens create in order to achieve the ideal VPD range without raising relative humidity to dangerous levels. If a facility runs warm and dry as a result of climate conditions and growing equipment, then integrating a humidifier can aid in reaching the VPD sweet spot.

Polygon's Temporary Climate Solutions allow growers to control the temperature and humidity of their facilities in order to enhance cannabis cultivation. Learn more by visiting https://www.polygongroup.com/en-US/services/temporary-climate-solutions/ today!