A stroll through the Demonstration Gardens of Glencarlyn, Simpson, and Bon Air leads one gently along the curves that define the paths and plantings. The softness and seemingly indeterminate order comfort the eye and make one anticipate the next bend. By contrast, a stroll through the Organic Vegetable Garden (OVG), in Potomac Overlook Regional Park in Arlington, Virginia, is a study in protracted straightness. Bean plantings form straight lines, their pole supports vertical and sturdy. Tidy pathways surround other rectangular beds of eggplant, tomatoes, and chard. Groomed and towering, the garden visually satisfying and inspiring. But tucked in a corner of the OVG, near the country-red shed, lies a bed that is different from all the others. It is neither large nor long nor rectangular. Its crops are not in straight rows. It is a 4-foot by 4-foot square overlaid with a grid of 16 1-foot by 1-foot squares. This is the Square Foot Garden.