Timber gravel boards are a cost effective option. Available in two lengths; 1.83m and 3m, they are useful boards for a variety of other landscaping projects as well as just for use as gravel boards.
Gravel boards help prevent the risk of the bottom of a fence rotting as without it would be exposed to ground moisture. They also stop soil and gravel from moving under the panel.
1.83m x 150mm x 22mm (designed for panel fencing)
3m x 150mm x 22mm (designed for feather edge fencing system)