repotting

ive been trying to dig around on here to find out when its time to repot my plants from the little 3 inch sq pots they in now but i keep getting on to a thread then reading it all and the hours are just wizzing by, they pull u in some of these threads, but still not found the answer i was looking for.

my plants are now 12 days old and about 4 inch tall from seed and just wondering when would be a suitable time to repot the plants into the pots they will spend the rest of their days in?
is there a rough time guide or is it just something to play by ear?

thanks

I let some of my plants get 23" tall before I repotted from my 4" round pots. Check out my journal, it was a plant I topped, so it had extra foliage and and roots to support it. I had to water EVERYDAY tho. So to answer your question, you got plenty of time. Wait until those roots are comin out the bottom of that pot if you want.

I would wait a little bit to do this but you can actually take plant out of it's container and inspect the roots. If they look any thing like this then its time to transplant. mabey even less than this>> this plant is rootbound for sure.

When your plant starts slowing growth its prob a good time to transplant.....

you could wait transplant it but its really not that big yet..

cheers guys really helpful