How long after I switch from 18/6 to 12/12 can I s...

He will find electric drills 24 hours before converting to 12/12 to stimulate the plant to start flowering

In Veg around week 4-5 you should be able to see if it M or F. Hope this helps. Happy growing.

Sorry to say I ordered regular seeds and now have to figure it out.. will be only fems and autos from now on.. thank you all I will attach photos in 1 or 2 weeks I just switched today to 12 hours.

Yeah, like lizy said. Many plants will show sex in veg once they hit a certain point of maturity. I've had plants show sex a month into veg and I've had plants that refused to show their sex until they started to actually flower. Generally speaking though 5ish weeks of veg, or a week of flower and they should give you a hint.

7-10 they will show their sex. In most cases you can tell the sex 5 weeks in veg.