All materials used in the sustainable landscape should be manufactured, quarried, or found within the region as much as practically possible. Note that regional materials are not those purchased at a local supplier that originated somewhere else in the country or world. Employing materials obtained in the region has several advantages. First, local materials are visually harmonious with a site because their compositional makeup, color, texture, and so on are all around and part of the material palette that defines the regional character. A second benefit of utilizing regional materials is that they often cost less because transportation expenses are minimized. It is cheaper to ship stone from a local quarry than from one that is miles away in a distant part of the country or world. Further, the use of regional materials benefits the local economy by employing people who live in the area.
The use of regional materials applies to vegetation as well. Regional plant materials or “native plants” are those found growing naturally in the geographic region, which are inherently adapted to local climate, soil, insects, and so on. Regional plants might also include vegetation from other locations with similar climate and soil conditions, though care must be taken to ensure that such plants are not invasive or hosts to pests not normally found in the region. In addition to sharing the benefits of other regional materials, indigenous plant materials have the innate ability to survive unattended in the region and are often acclimated to growing in plant associations with other native vegetation.