The common name ivy is widely used. The term “ivy” applies to over 25 different species of plants in the United States. Ivies are usually grown for their foliage and can be used as houseplants, in hanging baskets and to cover walls. A thick growth of ivy offers protection to snails, slugs and rodents, so you may want to locate your ivy away from your garden or the exterior of your home.
English ivy (Hedera helix) is an evergreen and works well as a groundcover or climbing plant. This ivy, belonging to the ginseng family, attains heights of 20 to 50 feet. In addition to foliage, English ivy develops green flower clusters and small, dark blue berries. The plants cling by exuding a glue-like substance and do not cling to wood as easily as they do to masonry. Be aware that English ivy can be invasive.
English ivy has shiny or waxy dark green leaves with white veins. While its leaves are usually lobed, location affects this ivy’s leaf shape, with plants grown in full sun frequently developing wedge-shaped bases and without lobes, according to the Pennsylvania Department of Conservation and Natural Resources. Older leaves also have fewer lobes. Cultivars are available in plain and variegated forms, featuring patterned leaves, small leaves, light-colored leaves and dwarf or slow-growing habits. If you locate English ivy in a protected area, the leaves will not lose their color during winter months.
Algerian ivy (Hedera canariensis) is also called Madeira Ivy or Canary Island Ivy. This evergreen ivy generally climbs and spreads to 20 to 30 feet, but can reach up to 50 feet in height. The plant produces 3- to 8-inch wide leaves, each with three to five lobes. Its leaves are widely spaced along the plant’s stems. Algerian ivy has thick, leathery leaves and insignificant flowers. Variegated hybrid varieties and cultivars offer a range of foliage options.
This ivy is heat tolerant and can serve as a groundcover in shady locations. Algerian ivy prefers partial shade, but will grow in full sun or deep shade given a moist soil and a well-drained location.
Boston ivy (Parthenocissus tricuspidata) is a fast-growing deciduous broadleaf, capable of reaching heights of 50 to 60 feet. The leaves of this ivy are a deep green color in summer, with reddish-bronze new growth, orange- to red-colored foliage in the fall and dark blue berries, according to the Clemson Cooperative Extension. Cultivars of Boston ivy offer alternative summer and fall colors and smaller leaf sizes.
While this ivy covers a surface quickly and is not usually troubled by insect pests, it can cause damage to masonry. The Clemson Cooperative Extension does not recommended Boston ivy for hot, dry locations. Boston ivy prefers a moist soil, but tolerates light conditions ranging from partial shade to full sun.
All parts of the poison ivy plant (Toxicodendron radicans) contain an oil that can severely irritate the skin and can cause an itchy rash. You should avoid contact with the plant, but to do so, you must first identify it, and that can be difficult.
Poison ivy can grow in shrub form, but is more often found as a vine. The plant can climb trees and structures or spread over the ground. Poison ivy may be distinguished from harmless plants by its compound leaves with three leaflets. The leaves may be smooth, toothed or lobed. A single vine may contain leaves with several types of leaf margins and combinations of colors. This is why the rule of three leaflets is usually used to warn people away from poison ivy. When foliage is not present to help in identifying the plant, you can look for gray or white fruits and the aerial roots that give the vine the appearance of a fuzzy rope.
Resources and References
Clemson Cooperative Extension; Vines; Karen Russ, et al.; June 1999
Clemson Cooperative Extension; Ivy; Marjan Kluepfel, et al.; May 1999
University of Florida IFAS Extension; English Ivies to Know and Grow; R.W. Henley, et al.; October 2003
Pennsylvania DCNR Invasive Exotic Plant Tutorial; English Ivy; Jil M. Swearingen, et al.
National Park Service; English Ivy; Jil M. Swearingen, et al.; July 2009
University of Arizona, Pima County Cooperative Extension; Hedera Canariensis Algerian Ivy; May 2004
University of Florida IFAS Extension; Spread Holiday Cheer with Ivy; Dan Culbert; December 2005
Michigan State University Extension; Poison Ivy Control; Tom Ellis, et al.; June 2008
Poison-Ivy.org; Facts About Poison Ivy; Jonathan Sachs
Iowa State University Extension; Weed Control: Poison Ivy; Robert G. Hartzler; June 2001