Issue Date: March 22, 2009

Go native

The benefits of growing local plant species reach far beyond your garden.

By Fran Sorin

There's an ongoing discussion about the extent to which gardeners should use native plants in their landscapes. Some gardeners could not care less about native plants. Others think not filling a garden with native plants is a sacrilege.

A native plant is one that occurs naturally in the area where it is growing. In the United States, a Norway maple and all other plants from Europe or Asia are non-native species. Even some species native to North America may not be native to your area. Because a lot of Douglas firs originate in the Pacific Northwest and Rocky Mountains, when they're planted there they will function as natives and increase the beneficial insect population. If a Douglas fir is planted in New York, however, it may look great in the landscape and thrive, but it is not a native.

Black-eyed Susans are native east of the Rockies.

Not only does Douglas Tallamy, author of "Bringing Nature Home: How Native Plants Sustain Wildlife in Our Gardens," talk about how native plants promote biodiversity, but he also says it is critical to the health of the ecosystem that homeowners plant native plants. "Today, suburbia supports very little biodiversity," says Tallamy, a professor and head of the department of entomology and wildlife ecology at the University of Delaware. "Every time we plant an alien plant, we are reducing the local insect population and depriving the birds and wildlife of the food they need to survive and reproduce. Our challenge is to redesign suburbia so that it becomes a healthy, functioning ecosystem."

Most non-native ornamental plants were first brought to North America by the colonists. Many folks today choose plants because they're beautiful or in vogue. And because the gardening industry is so competitive, retailers churn out a huge assortment of non-native plants. It's only in recent years that knowledgeable gardeners have sought out native-plant nurseries.

This wild columbine is native to Illinois.

Insects depend on native plants to supply them with food. So, if one plant species disappears from the environment, the insects that depend on it for food will eventually die. And because many other creatures depend on insects for food, the loss of the insects could endanger the ecosystem.

As stewards of the land, we need to learn the importance of native plants, research the species native to our environment, and purchase and plant at least some native trees, bushes and perennials. There's no need to dig up what you already have in your yard (for most of us, that would be too costly), but in the future, when you're looking to purchase plants, buy as many natives as possible. My own garden in suburban Philadelphia was about 70% non-native. In recent years, I've made sure to add native plants, and in designing gardens, I now use 80% to 90% natives.

If a local nursery doesn't have the native plants you want, go online to purchase them. Don't be intimidated: The process of designing with natives is precisely the same as the process used with non-native species. And the more you buy and use them in your garden, the more you will realize that native plants are as beautiful as any other plant in the landscape.

Fran Sorin last wrote about how to attract winter wildlife to your garden.

Want to know more about which plants are native to your state? Click here.

Want to know more about native flowers? Click here.