Certified GKH Gardening Expert
You should try to space them at least 24 inches to provide each plant with ample sunshine and good air circulation.
Depends on how much room u have. I have all the room I want so I space them 4 ft apart and use cages made from rolls of fencing. Sometimes they still end up growing together with next plant if I let them. But whatever space u have will work. You may have to trim them up to manage them.But it will be an adventure worth taking .