Where to measure RH in a grow tent?

learn more about VPD here : http://pulsegrow.com/vpd

you should do what you're doing and measure different places in the grow tent to get an idea for the micro climates. But humidity is important why? because it's a component of Vapor Pressure Deficit which in turn determines metabolism and therefore the growth rate of plants. what you really want to do is measure humidity , then measure temp then measure leaf surface temperature with a laser thermometer, then calculate where you are and where you want to be on a VPD chart. Hope this helps ! 🚀

Since you have 3 of them place them at height-specific intervals throughout the tent to get an idea of temperature and humidity at the plant's roots, base, and canopy.