Best water-wise ornamental grasses for hot dry gardens

Red Fountain grass (Pennisetum setaceum) holds a dominant place in a mixed border that includes white roses, Society garlic, Flax and Star Jasmine.

The graceful beauty of Ornamental Grasses

In recent years ornamental grasses and other grass-like plants have grown in popularity particularly as accents and borders in rock mulch style gardens. Many are fast-growing, very drought tolerant and will even thrive with considerable neglect. As a rule of thumb, they need fast-draining soil.

In Fall, the seed-bearing plumes of fast growing Pampas grass (Cortaderia selloana) rise to 20 feet high with little need for irrigation or fertilizer. By mid-winter, this perennial should be cut back to 18 inches tall. It will re-grow to the 8 to 10 feet in height during the following summer.

Avoid planting the Pampas Grass (Cortaderia jubata) which is an invasive weed. Given the right conditions — usually near a stream — it will self-seed and spread wildly forcing out native plants.

Drought tolerant grasses

Common Blue Fescue (Festuca glauca) – this is the short, clumping, fine blue or silvery gray grass, often seen as an edging to borders. The ‘Elijah Blue’ selection is relatively long lived and very blue. Grows to one foot high. It is not necessary to cut it back in winter. In this photo it has been used as a dominant plant along with Deer grass and an impressive Agave to replace a conventional green lawn.

Deer grass (Muhlenbergia), right, looks like a larger cousin of some of the Fescues. It grows to about 2 feet tall during the summer, but unlike Pampas Grass and Fountain Grass it does not need to be trimmed back in winter. As a native plant of the American West, it needs very little water.

Blue Oat Grass (Helictotrichon sempervirens) – looks like giant blue Fescue grass, but grows to 2 to 3 feet high and wide. Bright blue leaves with tall stems of yellow flowers in the Spring. Needs rich soil.

Red Fountain Grass (Pennisetum setaceum) – has reddish brown leaves and rose-colored plumes. Dies down in winter and should be cut back to a few inches high. Be sure to get the red variety, the white fountain grass is invasive and has been displacing native grasses. For best appearance Fountain Grass should be planted in dense clusters or as part of a mixed border.

Flax (Phormium tenax and lots of hybrids) – These New Zealand natives can be 5 to 7 foot tall giants, but with the proliferation of hybrids, smaller, more colorful plants are now available. You may have to ask for some of the newer colors – and they are glorious. For example, ‘Morticia’ has purple-black leaves; ‘Dazzler’ has scarlet leaves striped with maroon; ‘Tiny Tiger’ (only 1 foot tall at maturity) has variegated leaves that become tinged with pink as the weather cools and ‘Tom Thumb’ gives you green, wavy-edged leaves with a reddish border. You will have to put most of these in large pots out of direct sunlight; they do not do well in hot summer areas such as Phoenix or Las Vegas.

Japanese Blood Grass (Imperata cylindrical ‘Rubra’) – leaves emerge in spring with brilliant red tips and a green base. The red color intensifies as it grows to 1 or 2 feet tall. Rarely blooms and should be cut back almost to the ground in mid-winter. The photo, taken in early Spring, shows young Japanese Blood grass.

Golden Mexican Feather Grass (Nassella tenuissima) is the basis for this drought-tolerant front yard. Simplicity is the key: in addition to the Feather Grass, large agaves and blue-green ice plants make up most of the other plantings. Almost no maintenance involved! Once a year the owners cut the grass back to about 6 inches high.

Not a grass but similar

Society Garlic (Tulbaghia violacea) – a member of the lily family, has very fine bluish-green leaves with shoots of lavender flowers in Spring and summer. On the right, it is shown in a pot filled with rich soil. It retains its leaves all year round. It also emits the scent of garlic to the nearby area.

Other members of the lily family, including Daylilies (Hemerocallis) are also excellent grass-like plants for hot climates. Some, however, really need a lot of shade.