Trichomes are the "best", most efficient way to judge ripeness. Pistils can be damaged, die and turn colors from something as simple as too much heat for a few hours, an over feeding, or (heaven forbid) pollen.
By understanding the the transition of THc to CBD's, CBN's , you can harvest for a more precise effect.
c/p from DJ...
HARVESTING
As the plant matures through its window of harvest its chemistry changes. As the window closes, the more desirable compounds begin breaking down into less desirable ones. Primarily it is THC breaking down in CBNs and CBDs.
Which particular combination of chemicals is the most desirable is purely a matter of taste and choice, developed over time and with experience. Set and setting also play an important role in determining which type of product is best appreciated.
Pleasant head highs are often desirable for social occasions, whereas a narcotic late-window Indica may work better as an evening medicinal herb. The main point is that these differences are chemical in nature and more research is needed to more fully understand this phenomenon.
Another important point is that much can be done to further enhance the chemical process, especially in regard to bouquet, aroma and flavour, given the proper curing process.
