Depends on the Pheno you are growing. The Bubba that I grow is done in 50. My friend has a different genetic of Bubba and his is a 65 day finisher. Are u running CO2 and do you turn it off the last week or 2? Most of the time that I see weed that doesn't look done but seems that it grew plenty long enough to be finished, it is because it is coming from a perpetual garden with CO2 so the CO2 level isn't changed for the last 2 weeks to finish properly.. My 2 cents: Gotta know your pheno, gotta know what you are looking for (high THC earlier harvested) vs ( degraded THC harvested later) and you have to cut CO2 off at the end if you are using it..