What is the best length of time to keep the plant in the vegging stage, does it go by size of plant or lenght of time on 18/6 before moving to 12/12. Reason i am asking is because i have 3 in soil at about 2ft high and 4 in hydro but they are only 7" tall at moment. they all share the same room and i dont want to change lighting and f**k up my hydro's. They were sprouted just over a week apart and the soiled ones have grown like lightening. The hydro has over the last few days got a spurt on after giving them some nutes and i was hoping that soon they would catch up and i could then change the lighting from 18/6 to 12/12 so they were at the same harvesting time. I dont know the sex of them yet i have read on here that you can sex some at about 3 ft at vegging stage and other reports that you cant sex then till they go 12/12 and go into flower. i am not that bothered about the sex yet i am just enjoying watching them grow day by day. Obviously if there are males in the brood i will seperate them as and when, but it is fun to just watch them develope at the moment.. Main question i need to know is how long can they stay 18/6 ?
Well they can double or even triple in height during flowering so you have to factor that in. If you use methods such as topping/fimming or low stress training you could veg quite a bit longer. If you fimmed the 2 footers it would give the shorter plants time to catch up.