Low flagstone walls are simple to build
Inspired by stone walls she saw at England's famous Chelsea Flower Show, Marilyn Herlihy Dronenburg of Fallbrook, California, dry-stacked flagstones to frame raised beds in her vegetable garden. She used "patio-cut" flagstone (1 1/2-in.-thick slabs roughly 8 to 18 in. wide and long), which stacks easily, making it ideal for these mortarless walls. The beds measure 5 1/2 by 11 feet and are about 2 feet tall.
Limit the height of the walls to 3 feet or less (a taller wall requires a special footing).
Many building material and garden supply centers sell flagstone; prices vary according to cut, thickness, and color. Dronenburg used about 3 tons of Arizona flagstone per bed ($190-$280 per ton, plus delivery).
Powdered limestone or gypsum
Heavy work gloves
Narrow cold chisel or brickset