Dr. Greenhouse launched the Dr. Greenhouse VPD Calculator app. The VPD Calculator app helps growers understand their indoor growing environment and its effect on plant responses and HVAC equipment operation.
“Our Website VPD Calculator is the most visited resource on our website. Our team decided to create a VPD Calculator mobile app for growers and farmers to quickly calculate the VPD of their environment,” notes Dr. Nadia Sabeh, President of Dr. Greenhouse, Inc. “Knowing the best environment for plant direction and health is critical to ensuring optimal harvest results and timing.
Vapor Pressure Deficit (VPD) represents the “pressure” the air puts on the plant to transpire and move water and nutrients from the roots to other parts of the plant. For example:
- With low humidity and high VPD levels, there is more pressure on the plant to transpire and use more water. If plants are not well watered under high VPD levels, they may begin to wilt.
- With low humidity and low VPD levels, there will be less pressure on the plant to transpire. If plants are overwatered under low VPD levels, they are prone to pest pressure.
VPD can be a valuable metric for growers to predict water use, orient crops for optimal growth, and operate HVAC equipment to achieve the desired indoor plant environment.
The Dr. Greenhouse VPD Calculator app supports all crop types and includes VPD lookup tables for tomatoes, leafy greens, and cannabis. The VPD Calculator app allows growers to use their existing air temperature and humidity sensors to understand if room conditions are more suitable for vegetative, flowering or stress-induced plants. The VPD Calculator app provides color coded results to indicate if the room is wet (blue), vegetative (green) or reproductive (yellow) or dry (purple).
For facility designers and grow house managers, the VPD Calculator app can predict evapotranspiration rates to estimate water usage and plant dehumidification needs. With this information, HVAC equipment can be designed to meet the climate control objectives of the facility.
Sabeh comments on VPD, crop production and facility HVAC design: “When the right VPD is targeted for a given crop, variables such as light source, nutrients, water, HVAC and dehumidification can controlled to minimize operating costs while maximizing plant growth and health.”
For more information:
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Sacramento, CA 95816