Vapour Pressure Deficit Basics
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Temperature and humidity only mean something together, which is what VPD expresses as a single number describing how hard the plant works to move water. Aiming for around one point one kilopascals in flower keeps transpiration steady without stressing the leaves. Charts adapted for extended flowering periods are available on https://hazesativaseeds.com if you prefer that over guessing at percentages. Leaf surface temperature runs a couple of degrees below air, which most simple calculators ignore.