hmm it snowed and the plants are still alive? awsome. as for when to harvest its up to you. do you like to get a stoned couch lock high or a cerebral mind high. If you like cerebral highs harvest when most of the trics are milky white if you want a really stoned high go for 60-80 percent amber trics. or if you want a combination go for 50-50 the more you grow and smoke the more you will learn what you like better. gl man.