Soil that contains a high percentage of fine particles smaller than .002mm in diameter and colloidal substance and becomes sticky when wet. Clay soils can be mixtures of clay, sand and silt, with clay having the greatest percentage.
The flowers of Salvia darcyi are similar in appearance to Salvia greggii, however the shrub itself is more herbaceous than shrubby. I know of no common name for S. dacryi. Some sources say it is cold hardy to Zone 7, however it thrives in Denver Botanical Garden’s Zone 5. S. darcyi is native to the mountains of Northern Mexico and will do well in amended soil. Hummingbirds love it.
I have it planted in my xeristrip for a number of years. It will flower more vigorously with irrigation everyother week, when needed during hot drought years.
There are many different sedum species and varieties of this delightful spreading groundcover. I took this picture on a garden tour in Angel Fire New Mexico, and have not been able to identify it yet. It is easy to see from the picture how it got its common name, stonecrop. Sedum groundcovers spread nicely in a low to medium water use area of gritty, well drained soil, and will do just fine in afternoon shade.
The Calylophus genus is one of the best Southwest native plants for Panhandle gardens. Heat and drought tolerant, long blooming with little to no care, what garden would be without it? Sunny yellow 4 petaled sundrop flowers bloom in an explosion in spring, and respectably during the remaining growing season, especially when given a once a month inch of water during drought conditions. Each individual flower lasts only a day, tight compact mounds sport the orange spent blooms as well as the new bright yellow flower.
Texas betony is a workhorse of the garden once established, putting on a plethora of scarlet blooms midsummer on. A member of the mint family with square stems, the foliage is fragrant, but the plant is not invasive as classic mints tend to be. Hummingbirds love Texas betony. Though native to the Southwest, it is found in moist crevices and steep, stony places in the mountains in moist, well-drained sand, loam, and clay. Texas betony is said to be cold hardy to -20°, however, I have not found it reliable in returning each winter. Yet, it is worth replanting.
Two southern native hibiscus suitable for the medium to high water-use garden. Large green leaves are superseeded by very large and showy flowers. H. moscheutos is cold hardy and has some of the largest flowers, up to a foot across in red, rose and white, usually with a red eye. H. coccineus blooms scarlet 3 inch flowers -- not cold hardy but worth trying as a specimen container plant.
Sand lovegrass is a warm season bunch grass typically found in sandy soils east of the Rockies over a wide range of the U.S. The grass clumps themselves are usually 12-18" tall with the plumes rising to 3-4 feet. Will grow in clay and poorer soils. Very pleasing wispy, arching habit with a soft sway and rustle in the wind. Can grow in partial shade. Seed heads are somewhat purple, fine textured. Will reseed. Low or no water-use.
Mahonia repans is one of my favorite plants with four seasons of interest. Low growing and spreading evergreen shrub is native throughout the Rocky Mountains. Bright yellow berries in spring are followed by black berries in summer and reddish winter foliage. The leaves are thick, glossy and holly shaped. Creeping Oregon grape holly prefers amended, humusy soil that replicates its native habitat as an understory plant in woodlands, but is low water-use once established. It will spread to cover an area, but not invasive. Very attractive!