When should i check?(quick sexing?)

When should i be able to tell weather or not my plants are male or female? Do the signs show when flowering begins or should they be noticable well before? Thanks in Advance

.....usually 5+ days after you go 12/12, which is when flowering should begin........ check this Male or female? Cannabis sexing should have all the info you need. Sometimes they even pre-flower in the veg stage, so learn what to look for. If you have any more questions, try to have some pics and you'll get more replies...

There's lots of info right here in the newbie section fromvery basic to quite advanced...

Good Luck!
growinman