wait till its about 2 to 3 months old , take a few clones off each plant , root the clones , put 1 or 2 of the clones from each plant you take and flower them to find out their sex. this will help so that you won't waist any time putting them back to veg and waiting for them to recover. That and if there's ne males (hope not) and your not very careful the polin sacks can open and polinate your females and then your pretty much boned and your just better off doing a seed harvest and not putting them back into veg.How tall and how many nodes before you can switch to 12/12 to know the sex then re veg again? how do you properly do it without turning it into a hermie?
depends how big it is you could devide it into half and do it that waythanks for the info but im not doing the clone method because i only have one room to grow..
how many plants do you have? And what kind of light?How tall and how many nodes before you can switch to 12/12 to know the sex then re veg again? how do you properly do it without turning it into a hermie?
Let them veg for another two weeks, hopefully by then you'll start to see the plant growing "Alternating Internodes(nodes)". They should be at least a foot or better after 6 weeks in veg, and showing some pre-flowers. Like NoDrama said, you just look at the pre-flowers and you'll be able to tell if it's male or female and either pull the male or put the female into flower at that point. No need to clone. If you look in the Growfaqs there should be pictures of male and female pre-flowers to help you figure it out. If you need help you can PM me and I'll walk you thru it. You will need a small magnifying glass or a 30X hand-held scope, so buy one now and you'll have it when you need it.
If you have 4 feet of height to work with and the plants are 12" when you start flowering, you should have plenty of room. Like you just said, there's always "LST" if you have to tie them down a bit.thanks guys.. i only have 4 feet in room height so im kinda worried it my over grow the room.. ill just wait for the pre flowesrs.. if it gets around 10" then ill just tie em down