Sustainable Landscapes

Jennifer NicholsField Notes

“In wildness is the preservation of the world.”

– Henry David Thoreau

“In wildness is the preservation of the world.” Henry David Thoreau

Before we can thoughtfully discuss sustainable landscapes, we should define a sustainable landscape.

“A sustainable site links natural and built systems to achieve balanced environmental, social and economic outcomes and improves quality of life and the long-term health of communities and the environment. Sustainable landscapes balance the needs of people and the environment and benefit both.”
– from the Sustainable Sites Initiative
One simple and immediate step that every property owner can take to improve the sustainability of his or her site is to include native plants in the landscape. Plants that are native to a certain area have evolved to grow naturally in that area and are tolerant of local weather conditions and soils. In the Mid-Atlantic, native plants have evolved to thrive in wet springs, hot, dry summers, and cold winters. Some are adapted to dry, rocky sites while others grow in low, wet areas with heavy clay soils. There is a native plant for almost any site in your garden. Many tough native plants are used in rain gardens because they can tolerate standing water for short periods, and drought at other times. For property owners, using natives means no watering in summer, and reduced plant loss in harsh winters and during droughts.

Another, often unknown benefit of native plants is that they are uniquely suited to host native insects. This is why well designed butterfly gardens are not only planted with nectar producing flowers for adult butterflies, but also with host plants which are food sources for their caterpillars. For example, Monarch caterpillars feed on milkweed (Asclepias sp.), Pipevine swallowtails lay their eggs on pipevines, (Aristolochia sp.), and Spicebush swallowtail caterpillars live on spicebush (Lindera benzoin).

Along with butterflies, some caterpillars and other insects can also be quite beautiful. I will never forget the first time I saw a Hickory Horned Devil in the butterfly house at Tyler Arboretum. This caterpillar is almost as large as a hot dog, orange, blue-green, red, and black, with horns on its head and spines down its back. These creatures probably lived on the hickory tree that grew in my backyard for years, and I was not even aware that they existed!

Besides being beautiful, another major reason to attract insects to your property is because they are a major part of the food chain. Without insects, we would have no songbirds that feed on them. Songbirds and other animals that feed on insects generally do a good job of keeping these insect populations in check, so that our landscape plants are rarely harmed. Native trees in particular may host large numbers of insects, and because of their size and height, much of the nibbling done by these insects is never noticed. So for anyone who is interested attracting birds and having a property that is healthy and vibrant, beware of “pest free” plants. Plant Natives!

For more information about using native plants to attract insects, we recommend Bringing Nature Home, How Native Plants Sustain Wildlife in Our Gardens by Douglas W. Tallamy, Timber Press, 2007.