I started with 8 plants in about a 4 x 6 space and a 1kwatt light. By the end of the grow I had five females which took up every single inch and needed more. Working around them became really hard; the branches got bumped and broken, and trying to do maintenance on them became an extreme hassle. Make sure you leave enough space at the beginiing if you can't move things around later. My plants got to be close to five feet high by the end and about 2-3 feet wide apart. They GROW.