2 X 2 = 4 sq. ft.

The most you want to grow in there is two plants.

A lot depends on the sizes but 2 plants will fill that up easy...if they;re nice and healthy.

You can start flowering anytime you like. That is the beauty of the indoor grow.

For maximum results...

Your plant has matured when it developes alternating stem growth. However it can be forced to flower whether you have them or not.

Also, you want to flower when you have developed nice secondarys from above the fan leaves nodes.

Its really all up to you...

The longer the veg, the bigger the buds and the more of them.

Plant will AT LEAST DOUBLE in height when switching to flowering so plan accordingly.