Monitoring Environmental Parameters
in Agriculture and indoor Cultivation,

Optimizing Plant Growth: Understanding Vapour Pressure Deficit (VPD)

VPD, or Vapour Pressure Deficit, is a measure of the pressure difference between the water vapor in the air and the air’s saturation point, commonly known as the dew point. It is calculated as Vapor Pressure (saturation) minus Vapor Pressure (air). This pressure variance is instrumental in driving transpiration from the stomata of plants.

Unlike Relative Humidity (RH), which indicates the percentage of air’s water content saturation at a specific temperature, VPD provides a more nuanced understanding of the forces behind plant evaporation. While RH is valuable for humidity management, VPD stands out by directly correlating with plant transpiration rates, making it a proactive tool for empowering plant growth, rather than a mere climate parameter.

It’s noteworthy that the optimal VPD range for most plants falls between 0.4 kPa and 1.6 kPa. However, this range varies for different plants and their developmental stages. As a general guideline, during later stages of development, maintaining VPD on the higher side of the optimal range is recommended for optimal plant health and productivity. LoggerFlex Smart Devices, with their capability to measure temperature and humidity, can effectively monitor VPD, providing real-time insights and enabling growers to optimize indoor climate conditions for enhanced plant performance. The system’s cloud-based data acquisition and reporting features further contribute to informed decision-making in indoor agriculture.