Plants that will live in areas that experience 90-120 heat days (AHS Heat Zone 8) each year where temperatures exceed 86 degrees F. Except for a few limited areas in the Texas Panhandle, our AHS Heat Zone is 8. Plants rated lower than AHS Heat Zone 8 may not survive the summer's heat.
The Crassulaceae family of plants fascinates me, and the sedums are one of its larger genera. I first saw ‘Frosty Morn” featured on a gardening program from Iowa, so I wondered whether it’d be drought tolerant. Shortly afterwards, I found it at our local nursery and planted in my xeristrip. It has never faltered. The only disfiguring occurrence is a little nipping by grasshoppers during early summer, which has never seemed to harm it, or other large leafed sedums.
Calamint, a member of the mint family, sparkles with white/pale lavender flowers in late summer into fall. Solid green foliage emits a pleasing mint fragrance. Attracts bees. Sometimes referred to as lesser calamint. Calamintha nepeta spp nepeta covers itself with light blue flowers.
Santa Fe phlox is rarely available even at native plant nurseries, but when it is, don't pass it up. Sun loving and drought tolerant, the Santa Fe phlox blooms late spring throughout the summer with once a month watering. Five petaled, small pink flowers about an inch across with a small white eye can cover the plant. Native to canyons, mesas, and rocky desert slopes from West Texas to southeastern Arizona and into northern Mexico. Seeds of the phlox pop out when they are mature, making seed collection and propagation difficult.
Native to the plains, Coreopsis tinctoria, has naturalized throughout most of the U.S., especially in disturbed soil. Prefers moist sandy soil. An annual, it may last more than one year. Very showy flower with yellow outer rays, with a maroon blotch towards the center ray. Sow seeds in early spring. Heat tolerant, once a month watering is recommended for well drained soil.
Raspberry hybrid bush sage is very similar in appearance to Salvia greggii, blooming April through November. It's two-lipped flowers with a pleasant deep raspberry color, and the mahogany calyces contrast nicely. 'Raspberry Delight' is a hybrid cross between Salvia greggii 'Furman's Red' and and a high altitude collection of Salvia microphylla from central Arizona. Woody and brittle branches with small oval shaped leaves that hang on to the plant sometimes through the winter, as they do on S. greggii.
Curl leaf mountain mahogany is a medium height evergreen shrub native to elevations between 5000-10,000 feet throughout the Southwest. Small oval shaped dark green leaves lightly curl under at the margins are evergreen and aromatic. Small yellow flowers in spring time that develop into grain size fruits with a feathery tail attached to one end (similar to other mountain mahoganies). Slow growing and long lived, it can reach a height of 20 feet or more, but is more typically 6-12 feet. Densely branched. Cold hardy, drought and heat tolerant.
Western sand cherry is a shrub native to the northern plains favoring sandy soils. Cold and heat tolerant, and low water-use once established. Beautiful, fragrant white flowers in spring time, producing edible black cherries (however, some references advice not to eat the fruit if it is bitter).
Delicate and fragile in appearance, columbines are some of the most durable, versatile plants in the West. Aquilegia chrysantha is the Texas native columbine, happy in both sun or shade, moist areas or dry. Aquilegia chrysantha is native to the Chihuahuan and Sonoran Desert canyons from west Texas, southern New Mexico, southern Utah, and Arizona south into Sonora, Coahuila, and Nuevo Leon along with a disconnected population in southern Colorado.
A great plant for those people who must have their foliage fix. Despite their large foliage, cannas will do quite well in a medium water-use area with well amended soil.There are dwarf varieties and others that will reach 7 feet. Leaves shred easily by hail, but will recover after several weeks. Cannas sprout from thick rhizomes. Although subtropical, cannas easily winter over in the Texas Panhandle and spread to form a thick root mass.
Rose of Sharon, or Althea, is another reliable old-fashioned garden plant well suited for the Texas Panhandle. My favorite cultivar is Diana because of the brilliant, pure white 4-5” flowers and somewhat glossy green leaves. Diana is also one of the smaller varieties up to about 6 - 8 feet, while others can reach 10’ tall. Similar to most altheas, 'Diana' is a prolific bloomer.
Exciting perennial ornamental oregano for your low water-use or Mediterranean style garden. Spreads slowly by rhizomes and is easily propagated by root cuttings in fall or early spring. The flowers elongate as the summer progresses, eventually drying to a papery brown by summers end. In a wet fall, some new flowers may still appear. O. libanoticum is best placed to drape over a rock to showcase it’s drooping nature.
A non-invasive tansy from southern and central Europe for your low water-use bed and border that will reseed somewhat. A short lived perennial. Gray cut-leaf foliage provides an attractive white element in the garden.
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.
Shadscale lives in alkaline caliche soil in most of its native range throughout the Southwest and has a high tolerance of saline or sodic soils. Given improved soil conditions, it will grow larger. Do not improve the soil to insure it keeps its neat, compact shape. Shadscale blooms yellow flowers in early summer which mature into seed heads. Its silver-gray leaves are semi-evergreen.
Illinois bundleflower should be grown for its unusual characteristics of seedpods and leaves, if nothing else. A member of the legume or bean family, the seed pods turn dark brown, leathery and twisted in appearance and rattle in the wind in late fall. The compound, alternate, pinnate leaves fold when touched or when exposed to strong sunlight. Small white flowers in summer. Attracts butterflies, birds love its seeds. The plant can grow to be quite large if in high water-use areas.
Gooseberryleaf globemallow is very close in appearance to scarlet globemallow, Sphaeralcea coccinea, but much taller, up over 2 feet. The leaves are silver green and hairy, resembling the leaves of the current shrubs in shape, so named from the family name of currents and gooseberries, Grossulariaceae. Flowers are orange in color and bloom from May and June, sometimes later in the summer. Native to hot, dry areas semi-arid regions throughout the Southwest and the Great Basin Desert. Prefers good to sharp drainage.
Mountain mahogany is native to the Texas Panhandle and throughout the Southwest, found in elevations from 3000-9500 ft. Another common name is Alderleaf mountain mahogany, because its leaves resemble that of an alder. Mountain mahogany, whose wood is very hard (Palo Duro) is found in Palo Duro Canyon. Extremely drought tolerant, it will survive on 10 inches of rainfall. An aromatic shrub with shredding reddish bark, but can grow to tree size. Mountain mahogany's flowers are small, rayless and insignificant, as they are in the other species.
Gambrel oak is a common native oak species throughout the Rocky Mountain foothills and here in the Texas Panhandle as well. Often times it grows more to a tall shrub, with sufficient moisture it can mature into a small tree. Beautiful somewhat glossy lobed green leaves to 3-5 inches long. Beautiful fall foliage. Will put out a profuse amount of acorns. Gambrel oak can form a thicket. Cold, heat and drought tolerant. Inconspicous tiny red flowers appear shortly after leafing and are normally hid by the leaves.
Golden sulfur buckwheat is one of those plants you'll come across while hiking in the West and wonder why it isn't in your garden, its so adorable!
The leaves are gray-green, spatula shaped and woolly underneath, to about 2-3 inches. They form a rosette at the base. In early spring, tall, stout stems extend upward up to 2-3 feet. The bright golden flowers are nearly luminescent, appearing first as ball-like umbels (clusters), then each ball opening up to a circle of golden flowers. As the flowers age, then turn orange.
Centranthus ruber is a versatile plant, able to be used almost anywhere in the landscape except full shade. Long blooming except during the heat of the summer. Deadhead after the spring bloom for better appearances. Reseeds some, but not a problem. Quite drought tolerant, it will still do nicely in medium and high water use areas, except for wet, soggy clay. It appreciates good drainage and moderate amending but will do well in poor soil. Centranthus ruber 'Alba' is a pleasant white blooming variety. Readily available at local nurseries.
Perennial with lyre shaped leaves, similar in appearance to scabiosa, native to central Europe. In fact, it's synonym is Scabiosa rumelica. Deep purple red pincushion-like flowers. Knautia macedonica may suffer from our alkaline soil if not well amended with compost and well drained. Will reseed some. Has a pleasant wild look. Popular with nectar feeding insects. Deadheading doesn’t seem to be necessary.
‘Red Rocks’ is another hybrid cultivar, named for the Denver, Colorado red sandstone area and amphitheater. P. 'Red Rocks' is highly suitable for the average garden, rather than a specialized penstemon bed. Again, do not deadhead unless reblooming has occurred and you desire a tidier appearance. Don’t over water or over amend the soil, but it will thrive companionably with other medium water-use plants.
Thyme is known more for its use as an herb, but also makes an attractive and aromatic groundcover. Sometimes referred to as Thymus pseudolanuginosus, Thymus lanuginosus is a low water-use thyme for the hot dry areas that rarely flowers.
Native evergreen shrub that makes an excellent hedge plant and wind break. Its blue-green prickly leaves keep the unwanted out (to a point). Please allow room for its spread.
A habitat plant for shelter and as a food source of food for birds and other wildlife that is an attractive addition to the home landscape, where an evergreen shrub is called for in a sunny spot. Sun yellow flowers in March. Cold hardy to -20°, algerita can be found growing from 4000 to 7000 ft. in elevation in Texas, the southwest and Mexico.