Leaf VPD Calculator

The VPD (Vapor Pressure Deficit) and LVPD (Leaf Vapor Pressure Deficit) calculator is a simple tool that can be used to measure the difference between the vapor pressure of the air and the vapor pressure of the leaves. This information can be useful for growers who want to optimize plant growth and minimize disease risks.

Here’s how to use the VPD and LVPD calculator:

1. Start by entering the room temperature in Celsius or Fahrenheit in the “Room Temperature” field. This is the temperature of the air surrounding your plants.
2. Enter the room humidity as a percentage in the “Room Humidity” field. This is the amount of moisture in the air.
3. Choose the type of leaf temperature you want to measure by selecting either “Actual Leaf Temperature” or “Leaf Temperature Offset” using the buttons provided.
4. If you select “Actual Leaf Temperature,” enter the temperature of the leaves in the “Actual Leaf Temperature” field. This temperature is usually measured with an IR temperature read.
5. If you don’t have an IR temp meter, then select “Leaf Temperature Offset,” and enter the offset value in Celsius or Fahrenheit in the “Leaf Temperature Offset” field. This value is typically between 1-3 °C or 2-5 °F cooler than the Room temperature.
6. Choose the temperature unit you prefer to use by selecting either Celsius or Fahrenheit from the “Temperature Unit” drop-down menu.
7. Click the “Calculate VPD” button to calculate the VPD and LVPD.
8. The results will appear in the “VPD” field. The LVPD and VPD are measured in kPa or inHg, depending on the temperature unit you selected. The LVPD is the VPD measured at the leaf surface, and the VPD is the VPD measured in the air.