I have one that's 80cm x 80cm and I put 4 plants in 16L rocket pots, each with a diameter of 27cm. I do LST so they don't grow too tall, and I get good yields! Just make sure if you plan to grow in substrate, I'm currently doing hydroponics and I only put 2 in 20L buckets, just make sure there's a little space between them, that's all.