Ornamental grasses are nearly perfect perennials

When choosing perennials for our gardens we set high standards. We search for plants with attractive foliage, delightful flowers, showy seed heads, impressive fall color and winter interest. We look for plants that are nearly maintenance-free and rarely bothered by pests or diseases. We seek perennials that thrive in our ordinary garden soils, require little if any fertilizer and seldom need supplemental watering. If there were perennials that met all these standards, would you jump for joy?

Start jumping! These nearly perfect plants not only exist, there are several varieties available at your local garden center for just about every garden situation.

Ornamental grasses boast these characteristics and offer texture, contrast, color and architectural form to the landscape. There are so many species and cultivars that selecting a grass can be daunting. Let's start with some basic differences.

Warm vs. cool season

Ornamental grasses are divided into two groups: warm and cool season. Cool season grasses start actively growing when temperatures are cool in spring and usually flower in late spring or early summer. Once temperatures hit 75 degrees, their growth slows down. Karl Foerster feather reed grass is one of the most popular cool season grasses.

Warm season grasses wait until the heat of summer before their active growth begins. They quickly make up for lost time and generally begin flowering in mid to late summer. Maiden grasses, switch grasses and fountain grasses are all examples of warm season grasses.

Growing styles

Grasses grow either as "clumpers" or "runners." Clumpers grow in obvious tufts that spread slowly and stay where they are planted. Fortunately, many of our favorite ornamental grasses fall into this category.

Runners have horizontal stems that grow either over or under the soil. Use these as ground covers or as erosion control on sloping sites. The striped foliage of ribbon grass is beautiful when given lots of space to roam or planted within barriers.

Architectural forms

Ornamental grasses grow in a range of shapes. They may be upright, vase shaped, mounded or tufted.

Upright grasses like Northwind switch grass stand straight as soldiers. They are especially useful in space-challenged gardens.

Choose a vase-shaped variety from the maiden grass family as a specimen plant or plant a group to provide privacy. From Little Kitten to Autumn Light, there are varieties from small to tall.

Tufted grasses, like Elijah Blue fescue, have stiff vertical leaves that grow from a central point. Edge a perennial border with tufted grasses or plant them in drifts among other small perennials.

The fountain grass family offers mounded types. Karley Rose is a favorite sporting smoky rose-purple flowers that rise above clumps of elegantly arching deep green foliage.

Grasses for shade

Sedges, though not true grasses but usually included with ornamental grasses, are made for the shade. Fine examples include Ice Dance with white-margined, dark green blades and Bowles Golden with golden yellow foliage.

If a taller grass is required, choose Northern sea oats. Its upright, bamboo-like, green leaves grow 3 to 4 feet tall. Copper-colored seed heads resembles oats - lovely when shaken by late summer breezes.

Grasses for sunny, dry sites

Our native prairie grasses are perfectly suited to hot, dry situations. Big bluestem has fine textured, slightly weeping, silvery-blue foliage that turns coppery-red in fall. Its purplish seed heads appear in late August.

Prairie dropseed has fountain-like, 2-foot tufts of fine-textured, emerald green foliage. Airy flowers held 2 to 3 feet above the foliage smell like buttered popcorn.

Heavy Metal switch grass has metallic blue foliage with delicate, pink-tinged flowers beginning in late July. This upright grass grows 6 feet tall.

Grasses for wet sites

Prairie cord grass prefers moist soil, but will tolerate wet conditions. This native grass reaches 4 to 6 feet tall with graceful, arching leaves and twisted brown flower spikes in late July.

Palm sedges enjoy damp feet and can handle a sunny location if their roots are in wet soil.

No matter what your garden style or growing conditions, there is a lovely ornamental grass waiting to meet your standards at your local garden center.

• Diana Stoll is a horticulturist and the garden center manager at The Planter's Palette, 28W571 Roosevelt Road, Winfield. Call (630) 293-1040, ext. 2, or visit planterspalette.com.