Dr. Greenhouse VPD Calculator 2.0

Welcome to the Dr. Greenhouse VPD App!

Utilize this application to accurately determine the Vapor Pressure Deficit of the air in your cultivation space.

To begin, select your preferred temperature unit: Fahrenheit or Celsius. Proceed by entering the air temperature and relative humidity, then click "Calculate." The resulting VPD (kPa) will be color-coded to reflect the climate within the grow room, categorized as humid (blue), vegetative (green), reproductive (yellow), or dry (purple).

The optimal VPD varies based on the plant species, growth stage, and occasionally, the time of day. Generally, leafy greens, microgreens, and similar non-flowering plants thrive in a "vegetative" setting. Flowering and fruiting plants flourish in a "reproductive" environment. Cannabis plants can produce more trichomes and terpenes when exposed to a "dry" and water-stressed ambiance before harvest. Furthermore, maintaining a "humid" nighttime atmosphere can enhance the translocation of nutrients and metabolites in strawberries and other fruit-bearing plants.