At 12” spacing, each 100 square foot square has 36 square feet of “edge”, or unplantable space. Four individual beds with 36 square feet unplantable space each, equals a total of 144 square feet that is unplantable.

At 12” spacing, a 400 square foot square has 76 square feet of “edge”, or unplantable space.

If beds are not entered individually, the proper area of unplantable space is underestimated, therefore; the plant quantity is overestimated. In the above example, combining beds results in only 76 square feet of unplantable space, instead of the actual unplantable space of 144 square feet.