Ornamental grasses are a terrific addition to any desert garden. They soften the landscape, have interesting seed heads, and can have subtle seasonal color changes. In addition, many of the grasses are very drought tolerant once established.
Before planting, be sure to understand the growth habit of the grass you have chosen for your garden. Grasses can be either clump forming or rhizome forming. The clumping grasses will grow in very nice, neat mounds or clumps. The rhizome-forming grasses spread by underground stems and can become very invasive.
One of the clear advantages of the grasses is that they require little care. They are not picky about soil types as long as the drainage is adequate. Once established they require a regular deep watering during the Summer to maintain a lush green color, and occasional deep watering in the Winter. Periodic applications of nitrogen during active Spring growth will enhance color and size. Low rates of application are preferred. Most grasses should be cut back to about 4 to 6 inches in late Winter or early Spring. This will stimulate development of new grass blades and freshen the look of the plant.
Listed below are grasses that do very well in our area.
- Purple Fountain Grass (Pennisetum rubrum) – Native to tropical Africa, Southwest Asia, and Arabian peninsula. Purplish blades are topped by creamy flower spikes Summer through Fall. Thrives in full sun. It will grow to be 5 feet tall and wide, although there is a dwarf variety called “Red Riding Hood” which is particularly nice when grown in a pot or as part of a color bowl. Hardy to 0 degrees.
- Regal Mist (Muhlenbergia capillaris) – Native to the Southern United States all the way up to Kansas and east to Massachusetts. Green blades are topped by wispy pink flower panicles in Fall. It is particularly lovely when backlit at sunrise or sunset. Full sun or part shade. Grows to about 3 feet tall and wide. Hardy to 0 degrees.
- Deer Grass (Muhlenbergia rigens) – Native to California, Texas, and south into Mexico. Gray-green blades grow to 4 feet tall and wide. Slender cream-colored flower spikes appear in Fall. Will grow in full sun or part shade. Hardy to 0 degrees.
- Mexican Feather Grass (Stipa or nassella tenuissima) – Native to Texas, New Mexico, and Mexico. Among the finest textured of all ornamental grasses. Produces a thin flower stem that arches downward, ending in a cloud of silvery green awns. Will take full sun or part shade. Matures at 2 feet tall and 3 feet wide. Hardy to –10 degrees.
- Bear Grass (Nolina microcarpa) – Native to Texas, New Mexico, Arizona, California, and Mexico. Has greenish-white flower stalks in Spring. Radical pruning should not be done on this grass. Just remove the bottom leaves as they brown. Will grow to be 3 feet tall and 6 feet wide at full maturity. Will take full sun. Hardy to 15 degrees.
- Japanese Blood Grass (Imperata cylindrica rubra) – Native to Japan. The leaves emerge green at the base and red at the tips. This grass rarely flowers. Forms a 1- to 2-foot clump. Hardy to 0 degrees.
- Leather Leaf Sedge (Carex buchananii) – Native to New Zealand. Will grow to 3 feet tall and wide with erect reddish-bronze blades. Will need regular, deep waterings, and would appreciate some afternoon shade. Hardy to 15 degrees.
- Lily Turf (Liriope) – Native to Asia. Grows 1 to 2 feet tall with lavender to blue flower spikes in late Spring or early Summer. Needs filtered sun or full shade. Hardy to 0 degrees.
- Sweet Flag (Acorus) – Found throughout the Northern Hemisphere. This is a bog or aquatic plant that can be used successfully in color bowls as an accent grass. Japanese Sweet Flag grows 6 to12 inches, ranges from yellow to green, and is variegated. Hardy to 0 degrees.
- Ribbon Grass (Phalaris arundinacea picta) – Native to North America and Eurasia. Forms a 2- to 3-foot clump of variegated green and white leaves. Can be used as a bog plant, but is best planted where its aggressive growth can be controlled. Hardy to –10 degrees. “Strawberries and Cream” is a nice variety growing 1- to 2-feet tall, taking on a pink tinge in cooler weather.
5620 E. Pima Street
Tucson, AZ 85712