Read read read, :thumbsup:

You can put them into 12/12 whenever you like pretty much. I read a thread just last week from a guy who goes straight to 12/12 when his clones are ready (NO VEGGING AT ALL).

Do they grow during flower? YES they tend to shoot up much faster then in Veg for about three weeks. Then, they slow growth, and start putting weight into the flowers. Many people on this site say to count on doubling your height during flowering.

Many also say that you want between 40-50% humidity during flower.

Fully grown is a relative term. I've seen fully flowered plants only 12 inches tall. I've also seen what could only be described as a tree(30 feet around and 15 foot diameter).

If your closet is 7 feet? Subtract the depth of your light (10 inches-ish?). Now 6 feet 2 inches. Deduct the height of the pot (8 inches?). Now 5 foot 6 inches. Deduct the space needed between the light and the plant(to avoid burning the plant). So a sealed air cooled hood might be around 4-8 inches. Where as an open faced reflector might be 13-15 inches. Deduct that from your 5 foot 6 inches(still guesses on other factors). Then cut that in half to compensate for flowering growth.

Best guess on how tall you want until you flower? I'd guess 2 foot four inches tall. Then you should end up with plants around 4 foot 8 inches- ish.:thumbsup:

I suggest you read about LST(low stress training) and topping to widen the plant. Suggested spacing between bushes is 2.5 feet. Meaning each plant should have it's very own 2.5 square feet to grow in.