Trees, shrubs, flowers and other kinds of plants are considered "ornamental" when planted for their foliage, flowers or other interesting characteristics. Most any plant can be used as an ornamental, but some plants are more common than others.
Common Lady's Mantle
Common lady's mantle, an herbaceous perennial, is characterized by large, deeply lobed foliage and flowers. Depending on the cultivar, flower color varies and may include shades of green or yellow. One cultivar, "Thriller," has gray-green foliage and star-shaped flowers. This variety, along with some other varieties of this plant, is popular in dried flower arrangements. Take care to plant common lady's mantle in an area where its growth can be restricted. According to Michigan State University Extension, it can become invasive. Common lady's mantle is hardy in USDA Zones 3 to 8.
Columbine is an herbaceous perennial. Depending on the cultivar, this plant can reach 6 to 30 inches in height and produces flowers in an array of colors, including yellow, blue, pink and purple. Foliage may be green, yellow, gold or variegated. Plant columbine in moist, well-drained soil in a sunny or partially shady location. If planting in a particularly hot location, partial shade is preferable to sun. This ornamental plant attracts hummingbirds and bees and is used in cut flower arrangements. Cultivars of columbine are hardy in Zones 3 to 9.
Blue fescue is an ornamental grass. It is preferred over some ornamental grasses for its semi-evergreen, light-blue foliage. The foliage reaches 10 inches in height and equally as wide, with the height and width doubling when the plant produces flowers. Flowers are light-green and fine textured; they tend to be only minor in their ornamental interest. Use blue fescue as an entrance way, border or specimen plant. The fine texture and dense clumping habit of this ornamental grass make it ideal in rock gardens. According to the Ohio State University, blue fescue is hardy in Zones 5 to 8.
This shrub produces a prolific amount of summer flowers that attracts hummingbirds, butterflies and bees. It can reach 8 feet in height and width, or larger if not pruned. The fragrant blooms range in colors including pink, lavender, purple and white. Butterfly bush is often used as a border or foundation plant. It is hardy in Zones 5 to 9.