The above answers are not exactly the truth, what type of light r u using, I always harvest at 5-7 weeks tops, but, I am growing in a 5x2 grow room with 2 400 watt lamps, a combination of HPS and MH is best, my plants are only about 2 inches from the lights with a multiple fan set-up for heat........Bottom line, your plants will be Sativa like in high, Celebral, I love Head highs so this is ok for me, if u desire a body stone, tuff nuggies!!! If conditions are optimal, 6 weeks is very reachable, Hell I usually grow and flower DP Blueberry in 6 weeks, great head high, wonderful taste, with that unmistakable body stone that accompanies Blueberry, lumens per sq ft should be at least 5000-8000, I use 9000, basically, it all depends on ur enviorment.. .