Length considerations: 6 to 12 feet practical range

Bed length is the most flexible dimension, primarily driven by available space and lumber economics. The practical range is 6-12 feet. At 6 feet, you have enough linear space for meaningful crop diversity. At 8 feet, you match standard lumber lengths and minimize waste. At 12 feet, lumber costs increase (12-foot boards cost disproportionately more than 8-foot boards) and long walls need mid-span support to prevent bowing from soil pressure. For beds longer than 8 feet, add a mid-span cross brace or vertical support stake every 4-6 feet to prevent wall bowing. For metal beds, manufacturers engineer for specific lengths; follow their specifications. Very long beds (16+ feet) become inconvenient because you must walk around the entire perimeter to reach the other side, adding unnecessary steps. Multiple shorter beds with paths between them offer more flexibility for crop rotation and access. If building multiple beds in a row, maintain 24-36 inch pathways between them (48+ inches if wheelchair access is needed). Wider paths accommodate wheelbarrows for soil amendments and harvest transport.