While I do agree that VPD and humidity control is needed for optimum growth of many plants cannabis included. I am here to say that some fine cannabis can and is grown without spot on readings of vpd and perfect humidity. I live in some of the most arid and dry conditions on earth and my enviros are impossible to keep perfect but thats doesn't keep me from growing top shelf cannabis. :D We just as farmers do the best we can with the cards we are dealt.
This plant was grown in 27% max humidity its whole cycle.