Herbaceous (non-woody) perennial plants add year-round interest to any landscape and are a popular choice of plants among gardeners.

Thousands of perennials are available, but native perennials have a special role in the garden.

By definition, a native Pennsylvania plant is one that grew in Pennsylvania before the European settlers arrived, as opposed to exotic plants which came from other countries after that time.

Native plants are becoming increasingly popular and easier to find.

Natives have many advantages. Because they evolved here, they are well-adapted to the state’s climate and are generally easy to care for once established. Perhaps the most compelling reason to choose natives is to preserve Pennsylvania’s biodiversity.

Development is reducing natural areas that shelter a wealth of native plants. The landscapes that replace the natural areas consist mostly of lawns and exotic plants.

Research has found that 90 percent of native insects are specialists that feed on three or fewer families of plants. The insects rely on native plant hosts and cannot eat the exotic plants that have become common in yards.

A reduction of native insects means that birds have fewer insects to feed their young, and that will lead to a reduction of bird species. In the next 50 years, what we plant in our yards will determine the kind of wildlife that can live in Pennsylvania. By planting natives, gardeners can help retain the beauty and diversity of Penn’s Woods.

Though native plants have the home advantage, matching their needs to the growing site is important. The soil around many homes is often removed prior to construction and may not be replaced afterwards. Determine the soil type. Is it heavy clay or silty loam? Is it high or low in organic matter? Does it tend to dry out quickly after a rainfall or does it hold moisture?

Other factors must also be considered. Is the site in sun or shade? How much room does the site allow for perennials to grow to their maximum size without crowding?

Combining plants that grow well in the same natural habitats will help create healthy, vigorous plantings. By placing plants in the proper environment, you will be rewarded with gardens that thrive with less care.

Spring, early summer and fall are the best times to establish native perennials. Test your soil before planting, and, if needed, amend the nutrients according to the results.

Many natives do not require the addition of fertilizer and may do poorly in highly-fertilized soil. Plants that require moist soil high in organic matter will do well if compost is added.

Cultivate the soil to a depth of eight to 10 inches and incorporate any soil amendments.

When planting, placing the plant in a hole at the same depth as when it was in the container is important. If the plant is root-bound, make sure you free the roots by gently pulling it apart.

Once the backfill soil is added, water thoroughly. Additional water may be needed during the growing season until plants are established.

If planted in the proper environment, many natives need little or no additional water once established. Many meadow species may even become leggy if the soil is too moist. A two-inch mulch layer of compost will help conserve water. However, be sure to keep the mulch away from the plant stems.

Do not collect from the wild. Collecting plants from the wild causes the depletion of native species and disruption of the ecosystem. Be sure to purchase plants from a reputable source and purchase only nursery-propagated native plants.

“Growing Green” is contributed by Diane Dorn, Lehigh County Extension Office Staff, and Master Gardeners. Information: Lehigh County Extension Office, 610-391-9840; Northampton County Extension Office, 610-813-6613.