The humidity levels of the spot where you stash your herb have a lot to do with how long its medicinal qualities will last. Too much moisture in the air around your herb will make it susceptible to mildew and mold. Too little moisture will dry the trichome resin right out and degrade the herb even if the air temperature is optimal.Welcome To RH STAYFRESH! An Innovator in 2-Way Relative Humidity (RH) Control. RH STAYFRESH can be implemented in the most central and most popular ranges of relative humidity levels (58-72%) to preserve the precise humidity environment for an array of herb related products with which its packaged. RH STAYFRESH provides an eco-friendly unsoiled and cleansed humidity of other products and without risk of leakage and harm to product. ach RH STAYFRESH Pak consists of a specially prepared solution which is impregnated with a balance of natural ingredients into a semipermeable membrane designed to release and manage a specific relative humidity level through the process of osmosis exchange.