I have 6 plants. Each starting out in a 3" tall 3" wide container. What would be a good height of the plant to transplant them before there roots get to long?
here is a general rule of thumb: 2-6 weeks 4 inch pot 6-8 weeks 2 gallon pot 2-3 months 3 gallon pot 3-8 months 5 gallon pot 6-18 months 10 gallon pot
i generally plant clones directly into 6 inch pots. after about 2-3 weeks of 24/0 vegging, i stick them in 3 gallon containers and into the flower chamber.
my rule of thumb is when the leaf tips reach the edge of the container it time to replant but I use keg cups
never used keg cups myself, seems i always have a billion pots laying around. from small 3 inchers, to 10 gallon behemoths.