labifleanswered grow question 6y ago Hey gardener! The photos of the trichomes can't help you figure out how many weeks until you harvest, but they will tell you if the trichomes are mature or not to know if your harvest should happen in the next few days or not. We're looking for between 70 and 90% white trichomes to harvest. In about 3 weeks, you can start asking yourself this question. Good luck, bella ciao!