Welcoming seasonal birds, dragonflies or other favorite wildlife to your garden can be a gratifying experience and a wonderful way to support the ecological health of your garden and community. Yet evidence is growing that our gardens can also be indispensable resources for wildlife, providing critical habitat to offset some of the losses caused by fragmentation of our wildlands. Although garden and wildland spaces are often separated by distance, they are not sealed off from each other. Garden and wildland remain connected by the movements of wildlife seeking food, shelter or nesting sites. Going “wildlife-friendly” improves continuity between separated spaces, fostering stability and variety of the habitats wildlife needs to thrive.

What Makes a Garden Wildlife-Friendly

Habitat, habitat, and more habitat. For the garden, our notion of “wildlife” shifts from larger animals, such as foxes, bobcats, deer, to the other end of the size spectrum: tiny but exponentially more numerous creatures like soil bacteria, insects and spiders, plus reptiles, amphibians, birds and small mammals. A complete garden make-over is not at all necessary to be wildlife-friendly. Wise selection and placement of native plants and physical features (e.g., shelters, perches) can create habitat, and work together with your existing garden to add depth and breadth to your garden's ecosystem.

The Unique Relationship Between Native Plants and Wildlife

An excellent discussion of this relationship is found in Douglas W. Tallamy's book, Bringing Nature Home: How You Can Sustain Wildlife with Native Plants. Among the core concepts for wildlife-friendly gardens:

• Insects and plants co-evolved over long periods of time, adapting in tandem to each other and to their shared environment. About ninety percent of insect species are specialists, drawn only to specific plant(s) for food or other needs. These insect-plant associations are critical, especially for insects that undergo metamorphosis and use different plants at different life stages, e.g., larval vs. adult. For the 10% of insect species that are generalists, those insects have evolved special adaptations that allow them to use a wide variety of plants.

• Across plant species, not all leaves are created equal. Each species' leaves contain a unique set of chemical compounds which can attract one insect species but not another. The specific set of leaf compounds present determines 1) if native insects can find and recognize the plant, and 2) if the insect can use the plant for food or reproduction. For some wildlife species, a closely-related plant, whether native or non-native, may be a suitable alternative if the host plant is not available.

• Our gardens are ecosystems. A healthy, sustainable ecosystem contains a diversity of plants and wildlife to meet the needs of its many inhabitants. For example, adult birds often favor berry-producing plants until reproduction, when they shift their diet to insects to obtain the protein they need for themselves and their young. However, many berry plants often do not host insect life when birds make this dietary shift. A single plant species, even if native, cannot necessarily support all life stages or habitat needs of the wildlife that use it.

Benefits to Your Garden and Community

A successful wildlife-friendly garden not only supports a diversity of animal species, but also these species' present and future generations. In return, wildlife sustains the health of its plant hosts through improved soil health, natural pest control and pollination. Ongoing interactions between plant and animal life can reduce or eliminate the use of chemical fertilizers, pesticides and other harmful manipulations to a garden's ecosystem, protecting local watersheds and conserving natural resources.

Programs from the organizations listed below provide guidance and how-to's for integrating wildlife habitat into gardens. These programs can also spread the word in your community by certifying, and honoring with a public sign, gardens that meet criteria for being wildlife-friendly. Although these certification programs differ somewhat in their criteria, they all offer best practices that can help you, and inspire your community, whether your garden is an apartment balcony, or a generous front or back yard.

• Audubon Society of Portland
• National Wildlife Federation
• The Humane Society of the United States

A Garden Guide To Beneficial Insects. Richard Merrill.

American Society for the Prevention of Cruelty to Animals, here and here

Bay Area Lyme Foundation 

University of California Division of Agriculture and Natural Resources

6. Maintaining a Wildlife-Friendly Garden

California Invasive Plant Council (Cal-IPC) 

PlantRight

The Gardener's Guide to Common-Sense Pest Control: Completely Revised and Updated. 2013. William Olkowski, Sheila Daar, Helga Olkowski. Taunton Press.