Edging forms an attractive and well-defined outline around driveways, paths and flower beds. Without edging, weeds and paving materials spread in your landscaped beds, contained mulch spreads out and desirable plants suffer severe damage from lawn equipment. Consider installing stone edging around your herb garden or flower bed for a low-cost means of enhancing the beauty of the area and demarcating the space. Depending on personal preference, install loose field stones for a cosy, country-like touch or commercially available precast stone pavers for a formal appearance.
Measure the area you want to edge to determine how much stone edging you need. Spread powdered chalk around the flower bed or area you want to edge, keeping the lines as straight as possible and measure. Divide the area by the length of one stone edging piece to determine how many you need. If you think you might expand the garden later, buy extra stone edging now since you may not find the exact match later.
Dig a trench over the chalk mark where you want to install the border. Keep the trench as wide as the stone edging and 1.2 to 2.5 cm (1/2 to 1 inch) shorter in height so the tops protrude from above. Tamp the base of the trench with a tamper to compact the soil and level it. Also tamp the walls of the trench with the back of a shovel until it is firm and resists shifting.
Spread a 5 cm (2 inch) thick layer of crushed gravel or sand over the base of the excavation to create a foundation for the stones and prevent them from sinking. Smooth the top of the gravel or sand with a shovel.
Lower a stone into a corner of the trench and step back to examine its height. To adjust stone edging height, add more gravel or sand to the trench and to raise the edging or remove excess gravel to lower the edging. Lower the remaining stones into the trench around the perimeter, as close together as possible, despite their uneven shapes. Keep stepping back to ensure the tops of the stone edging are level.
Pound the stones with a mallet so they set in place. Fill large gaps between stones with smaller stones and add sand or gravel into smaller gaps. Hose the area so any loose soil firmly sets around the stones to hold them in place and prevent shifts.