Hello EltonLaroo,
Space to move around them and harvest is all that is necessary. The old forum had tons of pictures with very many people's gardens in every kind of orientation and crowding.
I too have some on a friend's apartment deck, installed a water barrel, and have the Automatic Watering System connected to keep them watered.
I have one junior on this deck, and it did poorly, but I believe that it was due to the swirling wind which was a bit much in the inner courtyard.
I have put up a screen on the railing to help block the high winds, and am going to plant some peppers to see if they do well. I'll update this thread when I have results.
Texas.Micky