Another way Horticulturists at Walt Disney World have tried growing crops is in open A-Frame designs.   This technique offers several obvious advantages, not among the least, it saves space, keeps the product off the ground, and increases air circulation of the entire plant.

In the back of this photo, tour boat passes by at the end of the row.   The popular Living With The Land boat ride is another way to see the greenhouses (albeit in less detail).