Grasses add unique interest to gardens

By Kathy Hatfield
Gardening Columnist

Back to Gardening Articles List

Adding year-round texture, as well as mesmerizing movement and soothing sounds, grasses play an important role in providing a sense of place to Colorado gardens. As a group, grasses are easy to grow, generally free from pests and diseases, and adaptable to a range of growing conditions.

Numerous varieties are available, with new cultivars appearing each season as more people begin to appreciate the unique qualities grasses can add to a landscape.

The following grasses are clumping grasses, which form bunches, as opposed to spreading grasses, which can form a dense turf. They are drought tolerant once established and well suited to northern Colorado gardens.

Indian rice grass (Achnatherum hymenoides) was once an important food grain for native peoples of the southwestern United States. Its airy seed heads provide an attractive accent in the garden. This exceptionally drought-tolerant grass is a good addition to a wildlife garden, as the flowers and seeds attract birds.

Big bluestem (Andropogon gerardii) has lush green foliage in summer and rich reddish bronze fall color. It grows well in a range of soil and moisture conditions, growing taller with more moisture. Dramatic as a single specimen, it is also an effective screen when mass planted.

Silver bluestem (Bothriochloa saccharoides) is breathtaking in the fall when its delicate silvery seed heads contrast with its reddish orange foliage. This native prairie grass holds its brilliant color into winter. The silvery blooms appear from spring to fall.

Blue oat grass (Helictotrichon sempervirens) forms a medium-sized dense clump of bluish green grass, useful as an accent in borders and rock gardens. It is somewhat shade tolerant and evergreen to semi-evergreen in our climate.

Mexican feather grass (Nassella tenuissima) is one of the finest textured of the ornamental grasses, dancing with the slightest breeze. Extremely drought tolerant, it will self-sow readily, but unwelcome offspring are easily removed. Plant this where it will be backlit by morning or evening sun.

Switch grass (Panicum virgatum), a native prairie species, is tolerant of a variety of soil conditions. It provides excellent cover for birds, has good fall and winter interest and produces gorgeous material for fresh and dried floral arrangements. My favorite cultivar is 'Shenandoah,' unmatched for its fall color: airy reddish seed heads held above intense reddish burgundy foliage.

Little bluestem (Schizachyrium scoparium) does not like particularly fertile soil or moist conditions. Depending on the individual plant, foliage can vary from green to bluish in summer and tan to bronze to reds in the fall. Delicate seed heads are especially attractive when backlit in winter.

Indian grass (Sorghastrum nutans) is a tall, beautiful prairie native that tolerates a wide range of soil conditions, even heavy clay! In summer, the foliage ranges from light to medium green, turning yellowish, then bronze in fall. This grass provides another stunning addition to bouquets.

Prairie dropseed (Sporobolus heterolepis) is unusual in that its flowers have a delicate sweet scent in late summer. Another extraordinarily drought-tolerant grass, this one is slow growing, but long-lived and tolerant of heavy clay. The foliage turns from emerald green in summer to golden orange in fall to a light tan in winter.

Most grasses benefit from a good haircut in late fall to early spring. Removing old growth makes for an attractive plant when the new growth develops. Waiting to cut back the grass until spring allows us to enjoy the unique texture and colors of the grasses throughout the winter. For evergreen grasses, a haircut is not necessary, but a gentle raking or plucking out of old growth will suffice.