The words “sustainable” and “sustainable design” have become common and even popular terminology in the design and environmental professions, though their defi­nitions and relevance vary. Simply stated, “sustainable” means ongoing, enduring, and self-sufficient. Thus, “sustainable landscape design” is a process of creating an outdoor environment that is capable of enduring over time in a self-sufficient manner with minimal expense of energy and maintenance. Sustainable design is integrated into the

landscape with minimal impact on the land while supporting the health of all living organisms on the site. Similar terms for sustainable design are design with nature, green design, environmentally sensitive design, and low-impact design.

Sustainable landscape design is a desirable concept not only for the benefits to an individual residential site, but for the larger environmental context as well. It is important to realize that every residential site is not an isolated island but rather an integral part of an environmental continuum where all things and processes are inter­connected. How a particular site is designed and managed can have potential conse­quences that extend to affect the region, country, and world. Our present-day world has numerous environmental challenges, including global warming, dwindling natu­ral resources, air and water pollution, increasing cost of energy, water shortages, and so on. A sustainable landscape recognizes these issues and is designed to help alleviate them. True sustainability means environmental sensitivity for an individual piece of ground and everything else beyond.

To accomplish this, the sustainable residential site should:

• fit the regional context.

• have minimal site impact.

• restore damaged sites.

• coordinate with natural events and cycles.

• reuse and recycle.

• create a healthy environment.

The desire to create a sustainable residential site that is sensitive to both the near and distant natural environment is an encompassing design philosophy that affects all steps of the design process and numerous decisions about what elements to include in a design, along with their location and material. Like the concept of creating outdoor rooms or aesthetic guidelines, sustainable principles and techniques provide a frame­work to design within. However, sustainability does not mean that a site must look completely “natural” to be “sustainable.” A sustainable site design can appear natural if desired, but it can also be created in many other styles in any geographic location. Nor does sustainability imply that a residential site will look messy, ill kept, or simply not designed. A sustainable design can potentially have a great deal of control and look highly maintained if that is the intent. Sustainable principles do guide design choices while simultaneously permitting considerable freedom and room for design creativity.

A range of sustainable principles and strategies are discussed in detail in the fol­lowing sections of this chapter. As they are read and studied, please realize that many of these principles overlap and are mutually supportive. Undertaking one strategy often contributes to others as well. Thus, the various principles and strategies should be implemented collectively so that they can have the greatest opportunity of creating a sustainable residential landscape.