Can you and is it safe to transplant after I've started the flower cycle. My plants are 10" high growing with flouros and I'm sure the roots have grown into the sides. I'd rather wait and see if they are going to be females or not before I waste the time and soil to transplant. Is that high enough to start the flower cycle. It only took 4 weeks to get that high. They are not spindley at all. Does that hieght seem good for that amount of time growing. Unsure of what the strain is(really good bag seed). They have very large leaves and the new ones out of the top have 9 blades if that gives any indication.
If you think they are already becoming root bound at 10", then you do need to repot now, you will only be able to determine sex approx 14 days after starting flowering, if you have the choice between buying new soil and pots, or good bud i know which one i'd go for! Transplant now into containers that have a 3 - 5 gal capacity, then start flowering once they are over 12" ok. good luck
i transplanted mine from 2 gall pots in to 5 gall buckets 6 days in flower they went from 10 inch to just under 3 foot in 9 days.....
i dont recommend transplanting in flowering stage just cuz it can stress them to some degree.....but if it has to be done, just let them flower for an extra couple days for the days or two they were stressed......if needed.
I would take the chance and transplant now. I have a bagseed plant that is about 12" tall, and was in a one gallon pot. I rinsed off the rootball to put it into my new bubblebucket and it was already rootbound like a bitch. If they are healthy plants, the roots grow amazingly fast.