White Outer and Inner Black color protect the root from sunlight. You don't even need a garden to grow with grow bags. Lay them along with the windows or on the floor. Grow bags can be folded up and stored with minimal space each season. Drainage holes allow excess water to escape through the bottom of a grow bag. The bag is UV treated to withstand severe sunlight. The inner side of the bag is painted black to avoid the harm caused to the roots due to direct sunlight. This goes especially for people who are either building or growing a container garden. By using these grow bags encourages root pruning rather than root circling. It is so versatile which can move from one place to another or plant directly in the ground. These grow bags are self-standing it does not require any additional support just you need to fill the grow bag with soil.