Xeriscaping means planning your garden design around plants that need little water and can tolerate extended dry spells, say North Dakota State University's horticulturist Ronald C. Smith and landscape architect Rose Larson. Xeriscaping often requires the use of native plants adapted to local seasonal rainfall and unappealing to area wildlife. Many attractive plants are excellent xeriscape performers, providing eye-catching garden color and lower water bills.
Rocky Mountain Zinnia
Rocky Mountain zinnia (Zinnia grandiflora) is an aster family perennial reaching from 6 to 8 inches high. It has a mounding habit, with stems emerging from a woody base. Gray-green, needlelike foliage provides garden interest during the six months of the year when it isn't in bloom. From April to October, however, Rocky Mountain zinnia flowers profusely with small, round, yellow-petaled blooms. Petals contrast strikingly with the flowers' deep purple centers. The flowers draw butterflies.
This plant is native to dry slopes and mesas from Kansas west to Nevada and south to Texas and Arizona. Use it, recommends the Lady Bird Johnson Wildflower Center, in dry rock gardens or for slope erosion control. Give it partial shade and well-drained, dry, sandy, rocky or limestone-based soil.
A milkweed family perennial hardy to minus 40 degrees F, butterfly weed (Alscepias tuberosa) grows wild in dry woods, along roadsides and on prairies throughout the eastern and southern United States. Standing up to 30 inches high and 18 inches wide, it has narrow, lance-like green leaves. Between June and August, its large, flat clusters of fragrant, brilliant yellow-orange to orange flowers have butterflies flocking to the garden. Its seedpods are popular additions to dried floral designs. Monarch butterflies lay their eggs on the plants' leaves.
Use these plants, suggests the Missouri Botanical Garden, in sunny perennial borders or native plant and butterfly gardens. Drought-tolerant, they like full sun and dry, well-drained locations. They thrive even in poor soil. They form deep tap roots and so don't tolerate transplanting.
Rock rose (Helianthemum nummalarium) is a low--9 to 12 inches--spreading perennial native to Europe and Asia. Hardy to minus 20 degrees F, it has 1-to-2-inch greenish-gray leaves on creeping stems. Up to 3 feet wide, rock rose has small, pale pink or yellow rose-like blooms in May and June. Each flower lasts only 24 hours. In the right conditions, however, blooms occur in foliage-concealing numbers. Largely resistant to pests and disease, rock rose develops root rot in poorly drained locations.
The plants do best where winters are mild and summers are cool, according to the Missouri Botanical Garden. Give them dry, well-drained, sandy or rocky loam and full sun. They prefer soil on the alkaline side (pH above 7.2). Grow as a ground cover with plants 2 to 3 feet apart.