I am not an expert by any means, but I think the plants will tell you how much time you have left. Pick up a lighted microscope at radio shack for $15. When the triches are to your liking, then bring out the chainsaw. This is what I did anyway. With the advice I got from this site. It is pretty interesting to check em out that close too. But there are so many variables that no two timetables are the same...hope this helps.