What a Rush!
Ornamental grasses are quite popular for their color, texture, form and winter interest, said Greg Stack, Extension horticulturist.
"Yet there is another plant that gets overlooked, one that can be equally as interesting in the garden," said Stack. "They are the rushes. Rushes are not true grasses, but they look grassy.
"Close to 300 species of rush are found throughout the world, most of them native to wet or moist sites. They usually have smooth cylindrical leaves. Some are evergreen, while others become dormant with the first frost. Rushes can be found in sun or shade and in fresh or salt water. Although most are found along streams, marshy area or in shallow water, some rushes can actually tolerate seasonal drought. As a rule, they are happiest in some light shade, especially in the afternoon – pretty much, they like the same amount of light that hostas do."
They range in color from shades of green through blue-gray. Rushes can be small (six inches tall) or giants growing to six feet tall. In the garden, rushes are at their best in or near water. They are excellent alongside ponds and in a small garden, rushes can easily be grown in tubs.
"Some have attractive flowers and foliage that are useful in fresh or dried arrangements," he said.
"Rushes have had a long association with man. Native Americans used rushes for basketry, crafts, housing and transportation. Lately, rushes have caught the interest of growers who are now offering many new cultivars to gardeners everywhere. These new cultivars vary in hardiness and so you need to make sure that when buying them you understand if they are perennials or should be treated as an annual."
Let's start off by looking at some traditional upright forms of rush.
'Blue Dart' is a rush growing to 16 inches tall with blue-green leaves and a strong vertical habit. This rush is often a great alternative to the 'spike' or dracaena used in container plantings. It is well suited to many growing conditions from standing water to dry soils. It also is hardy to zone 5.
Moving up the height scale is 'Blue Arrows' a blue-green upright rush growing to 36 inches tall. It is heat tolerant and is quite drought tolerant when grown in the garden. It is also hardy to zone 5 and semi-evergreen over the winter.
Topping off the upright rushes is 'Javelin'. This rush grows to four feet tall, has green leaves and a very rugged, upright habit. It can be grown in standing water but also tolerates heat and drought. 'Javelin' is hardy to zone 7 but if left standing in the garden offers good winter interest.
"If you want real interest in the garden, you need to consider planting some of the 'show offs' in the rush world," Stack noted.
'Spiralis', also called the corkscrew rush, has dark green, wire-like foliage that grows in a tight tangle of spirals much like Shirley Temple's curls. This plant adds interest as no plant can. It prefers very moist to wet conditions and as such is a great pond or bog plant. It could also be successfully grown in containers that are placed in shallow bird baths. 'Spiralis' grows to 12-14 inches and is hardy to zone 5.
'Frenzy' or variegated corkscrew rush also has eye catching coiled green leaves. It goes the extra step by having a bright gold stripe down each of the leaves. 'Big Twister' is also a corkscrew rush but tends to sport very upright, bold, spiral leaves. This is an architecturally bold plant that grows to 24-30 inches tall and hardy to zone 5.
'Sword Leaf' rush has the unique common name of Flying Hedgehogs. This is a small North American native that grows to six inches tall with flat leaves that resemble dwarf iris. This rush produces very dark, almost black, round spiny seed heads that rise above the foliage and appear to be flying. It prefers moist to wet conditions and is hardy to zone 3.
'Soft Rush' or common rush is a clumping plant that grows vertically to about three to four feet. The medium green foliage turns a yellow brown in the fall. Soft rush grows in shallow water, or moist boggy soil and is suitable for pots or tubs. The tall arching stems sway in the breeze and also look dramatic when back lit at night.
"So, when you are in a rush to find that unique garden plant and have a spot that is lightly shaded, moist to wet, consider planting a rush," he said.