Attempting to grow grass under large shade trees or shady areas created by buildings, fences, and walls is difficult and frustrating. Because of unfavorable growing conditions, grass doesn’t grow well in shady areas and the area is often little more than bare soil and a few weeds. A shade-tolerant groundcover is an excellent alternative to turfgrass in shady areas. Once they are established, groundcovers require less maintenance than turf, they can out-compete most weeds, and some have attractive flowers as well. Groundcovers will require more time to establish initially but are worth the effort in the long run.
There are also several species of groundcovers for sunny sites (Groundcovers for Sun). Some groundcovers such as bugleweed and vinca perform equally as well in both shady and sunny sites. More information about groundcovers for Iowa can be found in this publication: Groundcovers
A partial list of groundcovers is provided below. Plants are listed in order from shortest to tallest.
Bugleweed (Ajuga spp.) is a low-growing, spreading plant that develops into a dense groundcover 2 to 8 inches tall. Leaves are typically dark green. However, cultivars with colorful foliage are most often grown in home landscapes. The leaves of these colorful cultivars may be combinations of bronze, purple, gray, burgundy, and white. Flowers are usually violet-blue, but may be pink or white. Bugleweeds perform best in well-drained soils in partial shade. Plants tend to be thin in dense shade.
Canadian wild ginger (Asarum canadense) is a native woodland wildflower. It often forms large colonies in moist woodland areas. Each plant usually consists of two heart-shaped leaves. A single flower is produced in April or May. The flower, usually hidden beneath the foliage, is bell-shaped and maroon to brown in color. The common name, wild ginger, refers to the ginger-like aroma produced when the leaves or rhizomes are crushed. Native to eastern North America, including parts of Iowa.
European wild ginger (Asarum europaeum) is another excellent groundcover with glossy, dark green foliage. Both gingers grow 4 to 8 inches tall and prefer moist, well-drained soils that contain large amounts of organic matter. Sites in partial to heavy shade are best.
Periwinkle (Vinca minor) is an excellent groundcover for partial to full shade. The species and most varieties possess glossy dark green leaves. A few varieties have green and white variegated foliage. White or lilac-blue flowers appear in spring and continue intermittently throughout the summer. Plant height is approximately 6 inches. Periwinkle does not tolerate wet sites.
Growing 6 to 8 inches tall, sweet woodruff (Galium odoratum) has leaves arranged in whorls around the stem. In spring, plants produce clusters of small, white flowers. As the scientific name suggests, sweet woodruff produces an attractive fragrance (similar to newly cut hay) when dried or crushed. The fragrant plant material is often used in potpourri and sachets. It can also be used to flavor wines and other drinks.
English Ivy (Hedera helix) is a semi-evergreen groundcover noted for its lustrous, dark green leaves. The plant reaches 6 -10 inches in height and prefers partial shade to full shade. The flowers are not noticeable. This groundcover is not reliably hardy in northern Iowa and may require protection from the wind and sun in winter. Additionally, plants can creep up the trunk of the tree shading out lower branches with time.
Japanese Spurge (Pachysandra terminalis) is an evergreen groundcover with lustrous green foliage. The plant reaches 6 to 12 inches tall and prefers partial to full shade. The whitish flowers, though not showy, appear at the ends of the stems in spring. Japanese Spurge requires protection from winter winds and sun.
While the glossy foliage of Japanese spurge is highly ornamental, Allegany spurge (Pachysandra procumbens) is a great native alternative. This species originates from the southeastern United States. Plants are slightly taller at 12 to 15 inches tall and the semi-evergreen leaves are a dull green to bluish-green color. Allegany spurge does not spread as aggressively as Japanese spurge, but it is more winter hardy and has fewer insect and disease issues.
Though it spreads slowly, barrenwort (Epimedium spp.) is an excellent groundcover for partial to heavy shade. Plants commonly grow 8 to 12 inches tall and have green, heart-shaped leaves. In spring, the leaves are often tinted red. Barrenwort produces small, columbine-like flowers in spring. Flowers may be white, pink, red, or yellow. Barrenwort will tolerate dry, shaded conditions. However, the best growing sites are those with moist, well-drained soils (containing large amounts of organic matter) in partial shade.
Several cultivars of spotted deadnettle (Lamium maculatum) are excellent groundcovers with attractive foliage and flowers. ‘Beacon Silver,’ ‘Pink Pewter,’ and ‘White Nancy’ have silver leaves with narrow green margins and pinkish purple, soft pink, and white flowers, respectively. Plants bloom from late spring to mid-summer. Spotted deadnettle grows 8 to 12 inches tall. It performs best in moist, well-drained soils in partial shade.
The closely related yellow archangel (Lamium galeobdolon) is an adaptable groundcover that grows well in dry, shady areas. The cultivars ‘Variegatum’ and ‘Herman’s Pride’ have green leaves with silver markings. Plants are a little taller than spotted deadnettle at 2- to 15-inch-tall and produce yellow flowers in spring.
Creeping lily-turf (Liriope spicata) is a grass-like, rhizomatous perennial. Plants grow 8 to 12 inches tall. Creeping lily-turf has narrow, dark green foliage and produces small, white to pale violet flowers (partially hidden amongst the foliage) in mid-summer followed by blue-black, berry-like fruit. The grass-like foliage of creeping lily-turf persists through the winter. However, by late winter it often looks rather scruffy. To promote new growth, remove the damaged foliage with a mower or grass shears in early spring.
Foam flower (Tiarella cordifolia) is groundcover noted for its distinctive foliage and flowers. This North American native has medium to dark green, maple or oak-shaped leaves that often have dark brown or burgundy markings. While the foliage is similar to the more common coralbells (Heuchera), the flowers are much different. The 6-inch flower racemes are pinkish-white and appear in spring. Plants spread readily by stolons and make great companions in mixed groundcover plantings and woodland natives like Solomon's seal, trillium, or Virginia bluebells. Plants grow 6 to 18 inches tall.
Lungworts (Pulmonaria spp.) are clump-flowering perennials with distinctly spotted foliage. The foliage of most species and cultivars is green with white or silver spots. However, some cultivars have essentially silver leaves with green margins. In addition to the attractive foliage, lungworts produce colorful flowers in spring. Flowers may be white, pink, or blue. Lungworts grow 9 to 18 inches tall and can be grown as a groundcover or specimen in partial to full shade.
Wild geranium (Geranium maculatum) is another native woodland wildflower. Plants grow 2 feet tall and bloom in spring. The five-petaled flowers are 1 to 1½ inches across and pink to lilac in color. The deeply cut, palmately lobed leaves may be up to 6 inches across. Wild geranium prefers moist, well-drained soils and partial shade. Native to eastern North America, including Iowa.
Hostas (Hosta spp.) can be used as a groundcover or as specimen plants. Some hostas, such as Hosta clausa, have a stoloniferous growth habit, making them ideal as groundcovers but even the more common clump-forming hosta works well as a groundcover because their large leaves quickly expand and shade the ground creating a sea of large green leaves. They are long-lived, easy to grow, and have few serious problems. Hundreds of cultivars are available that vary in leaf color, texture, and shape as well as overall plant height and flower characteristics. Hostas grow best in moist, well-drained soils. Most cultivars prefer partial to heavy shade.
Astilbes are great perennials for shady areas in the landscape. They range in height from 8 to 36 inches tall. Because it spreads quickly, Astilbe chinensis 'Pumila' is one of the best astilbes for groundcover use. The 8-inch-tall lavender-pink flower spikes of 'Pumila' appear in late summer atop dark green foliage. Astilbes prefer moist, rich soil that is well-drained in winter.
Groundcovers to Consider with Caution
Two other widely grown groundcovers are bishop's goutweed (Aegopodium podagraria 'Variegatum') and lily-of-the-valley (Convallaria majalis). Bishop's goutweed and lily-of-the-valley are very adaptable plants and will grow in very difficult sites. Unfortunately, they both spread rapidly and often become invasive. Once established, they are difficult to eliminate or destroy. These aggressive spreaders are not suitable for mixed plantings. They should only be planted in areas where they can be confined or allowed to spread freely.