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.
Rudbeckia is advertised as heat and drought tolerant, but I have not found it so. I’ve found it to require at least weekly watering during the heat of the summer. A shortlived, southern native perennial, it likes the humidity and rain from southern climes. These very large and stunning composites may be worth your effort, just place within the correct hydrozone.
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.
Dark green, semi-evergreen aromatic leaves are the feature most prized, along with the tiny yellow daisy-like flowers that bloom spring to fall. Damianita prefers full sun and lean soil and does well in heat and temperatures to zero degrees. Daminaita will lose its leaves in cold winters.
Mexican blue sage is a native of Mexico and in many references labels it cold hardy to USDA Zone 8, however, it has wintered over in Amarillo many years now, even in full northern exposure. It has died back to the ground once or twice, but comes back up from the roots. If good to well drained soil is provided, it should do fine. And I hope you can provide that, as Mexican blue sage is one of my top plants to include in xeric gardens. True bright blue flowers bloom summer and fall with once a month watering. Butterflies are attracted to it. Indispensable.
People either love trumpet creeper or hate it. The first three years, I couldn't wait for it to mature, filling with red-orange trumpet shaped flowers. It seems I've spent the next 20 years trying to kill it. Trumpet vine will die, but only for those who want it to live. If a gardener gives it the death wish, it will be sure to flourish. Native to most of the eastern half of the U.S., it is low water-use, thrives in heat. Must be in a sunny location to bloom profusely. Considered to be invasive, especially when over watered. Not particular about its soil.
Texas, or scarlet sage is a perennial to the Southern U.S. and Texas. In the Texas Panhandle, it is sold as a bedding plant, since it is not cold hardy. Some varieties will come back due to re-seeding. Many varieties are available, some are more drought tolerant than others, such as 'Forest Fire', while 'Lady in Red' requires medium water-use beds. Summer long blooming, choose your color among scarlet, red, rose, pink, coral and white. As with most sages, hummingbirds, butterflies and bees are attracted to them.
Utah serviceberry is a quite beautiful shrub extending from the Southwestern states northward throughout the Rocky Mountains and through various ecosystems between 4000 and 8000 ft in elevation. Deep green leaves, large oval shaped and toothed at the margins, many intricately branched, smooth gray to maroon bark. Large white flowers with five widely spaced petals open in May and June. Berries appear in the summer, ripening to pink, then red, then finally dark blue. Leaves turn red and orange in the fall.
Bear grass is similar in appearance to yucca and clumping grass, but is neither. Usually found growing in high desert areas, along cliffs and rocky slopes. Thin succulent grasslike yellow-green leaves emerge from a trunkless center, are pointed and sharp edged. A plume-like inflorescence with many tiny cream colored flowers emerges early summer. Cold hardy, drought and heat tolerant.
Beautiful xeric sage with aromatic soft gray green leaves, mostly evergreen. Summer to fall blooming with mauve/purple sticky but fragrant flowers. Takes a few years to reach mature height. Requires good drainage and dry soil in the winter. A Plant Select® Plant. Native to California and will grow in the High Desert regions. Cold hardy to Zone 5 and quite heat tolerant.
Caladium bulbs are tropical plants grown for their summer foliage, however they do send up an arum type flower (a member of the Araceae family). Foliage comes in many different variegation patterns in red, pink and white. Plant bulbs after May 1st, only about 3 inch deep. Caladiums like it hot and moist. Complete shade works OK, or morning sun only. For larger leaves. keep the bed or pot well moist, especially during bulb germination. High water use plants can be used for small areas of the landscape or pots.
This is an improved variety to our native gaura, it is known to be short lived for 4 – 5 years, but is worth replacing periodically for its spectacular fireworks display. Placed as a focal point, G. lindheimeri ‘Whirling Butterflies” was the plant most commented on in my front garden. Native more to eastern Texas and Louisiana, a terrific plant for city or country in a medium water-use location. Any plant with long wispy stems that flows with the wind is an asset to your border. Other cultivars to use are ‘Siskiyou Pink’ and ‘Pink Cloud’, two pink varieties.
Drought tolerant perennial with white cup shaped blooms usually found growing in poor soils. I planted it in heavily amended soil, and I think it was too rich for it. It was eaten up during the heat of the summer by flea beetles. I thought the too rich soil was the cause; however, Judith Phillips in Plants For Natural Gardens, wrote about this same occurrence in native soils. Phillips hypothesized this may be a way for tufted evening primrose to escape summer’s heat. However, my plant died, rather than just going to ground.
Salvia argentea is a first class drought tolerant biennial to add texture to your xeristrip. Light gray green tomentose (hairy) foliage adds contrast against accent rocks. This biennial will flower the second year, but I could do without the sticky, and somewhat unsightly stalk whose white flowers open in succession and quickly turn brown. Cutting off the stalks only encourages the plant to send up more sticky stalks. The leaves of the plant may appear to mimic Lamb’s Ears, however, they are not tough and resilient, tears easily, and are shredded by hail.
Veronica x ‘Blue Reflection’ should be an indispensable evergreen groundcover for you, as it has become for me.
I prefer dwarf chamisa to the full size species. Dwarf Chamisa fits better into home xeric areas and has green leaves, rather than gray or silvery. It's silvery stems combine well with its green foliage and yellow gold flowers. Although given the species and variety name "nauseosus" it has a pleasant fragrance. Dwarf chamisa blooms profusely in late summer and will readily re-seed.
Texas red yucca is technically not a yucca, but has many of the same qualities as yuccas. Thick, succulent dark olive green leaves grow out of the base, as it is stemless. The coral red flowers appear at the top of a long raceme, often 4-6 feet tall. 'Yellow' and 'Red' blooming yuccas are also available. Although it's natural range is north eastern Mexico and West Texas, it is cold hardy throughout much of the Southwest. Allow for sharp drainage in moister climates to prevent root rot.
Perennial vine native to the Southwest. Late summer to fall bloom with slender, thin whitish sepals, followed by attractive plumes that are feathery seed clusters. The vine is valued for it's delicate beauty of leaf, flower and plume and drought tolerance. Clematis drummondii is a larval host and/or nectar source for the fatal metalmark butterfly.
Purple or desert sage prefers leaner, quick draining soils. It is said to grow 2-3 feet tall and deeply branched with silver gray foliage and a profusion of violet bluish flowers atop spikes in late spring and summer. Low water-use, but does better with once a month irrigation. One of the finest flowers of the desert, it is the sage of Riders of the Purple Sage, by Zane Grey. Grows throughout the Great Basin Desert.
Littleleaf mountain mahogany is the shortest of the mountain mahoganies usually sold. Small, narrow, leathery looking evergreen leaves on many intricate branches. Small yellow flowers in springtime and feathery seed plumes in the fall. The shrub is densely branched and slow growing.
Littleleaf mockorange is native throughout the foothills, dry rocky slopes and open woodlands from 4000 to 8000' in the Southwest usually growing to only 4 feet. This native mockorange is similar in form to the European import, they are fragrant, but not of orange. Attractive white, 4 petaled flowers bloom in early summer, small slightly glossy green leaves. Coldy hardy, heat and drought tolerant.
Karl Foerster feather reed grass is a cool season bunch grass one of the best ornamental grasses for a medium or high water-use area. In a low water-use area, it will take longer to reach mature height and width (the more water it gets, the bigger it'll get). Karl Foerster feather reed grass suffers in the xeric bed during the hotter, drier drought years and may die out.
It's hard to pass up Johnson's blue geranium with the deep blue flower and interesting foliage. A hybrid cultivar, the most blue hardy geranium with delicate, finely cut leaves. Plant in your woodland border, medium water use. For a long time this was the most well know hardy geranium, or cranesbill, as this genus is commonly known.
When the name geranium is spoken most of the time, people are referring to the genus, Pelargonium, the red flowering perennial that is used extensively throughout the world. the common Pelargonium is only cold hardy to 28°.
Oenothera macrocarpa, and O. missouriensis have been used interchangeably. Native over a wide range including the plains and wooded areas, carries the common name, Missouri evening primrose, bigfruit sundrops and Ozark Sundrops.
If I had to pick my favorite plant, this is it. Long blooming and drought tolerant with only minimal maintenance of late winter cutting back, and maybe a bloom pick-me-up deadheading at mid summer. It will also re seed some so you’ll have more of them the next year. It’s fragrance is light and pleasantly of sage. Salvia greggiis are native to Texas in the Kerrville area. It is my favorite, but not the absolutely perfect plant. The stems are quite brittle and very easily break or snap off, even when you’re carefully weeding around it.