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The model 2475 Plant Growth Station displays VPD on
the unit. VPD can be calculated in SpecWare Custom Re-
ports for all models. Firmware 3.8 and SpecWare 9 Pro or
higher is needed to use VPD.
VPD (vapor pressure deficit) is the difference between
how much water vapor is in the air and how much water
vapor the air can hold at saturation. It predicts the rate of
water vapor movement from the plant to the surrounding
air and is a useful tool in plant watering decisions.
To view a VPD report, select Reports in the dropdown
menu from Tools on the menu bar in SpecWare. Select
Custom Reports (see button to right of Standard Reports)
on the Select Report tab. Create a new Custom Report.
Assign a name and reporting interval.
VPD