Depends how you're growing.
If you have a veg space and are taking clones, you could put 9 or more plants under each light. Just flower them when they're about a foot tall, Sea Of Green style. Do this for many small to medium plants.
OR, you could put 2 - 4, big, bushy plants under each light and harvest few, larger plants.
Personally, I'd start from seed, choose a few good, healthy, nice smelling females, veg them for a couple of months, take as many clones as possible, keep the best 18 and flower 9 under each light.