Sustainability is at the forefront of Mesa, Arizona's True Garden urban hydroponic garden. Here, food grows in special conditions, without one, usually common, ingredient -- soil. In fact, no soil is used to grow the fresh herbs and vegetables at True Garden. Instead a simple mineral solution is used. There are no chemicals, or preservatives used in the food here, either. The bright, white-walled garden area is typically off limits to visitors, however, guests can likely schedule a prearranged tour to take a look at the growing process and walk the isles of the tower gardens. Plus, True Garden occasionally hosts a farmers market where locals and visitors can get their crop of fresh greens.