High Plains Gardening
The gardening website of the Texas High Plains Region
AHS Heat Zone 8
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.
Russian sage is a must have shrub for every low water-use landscape. Russian sage is used extensively throughout our southwest landscapes, planted along with Buddleia, Carl Forester Reed Grass, Salvia greggii cultivars, Anisacanthus quadrifidis wrightii and Hesperaloe parviflora. It is hard to beat its use where a long flowering, showy, low care, drought tolerant shrub is needed.
Grown extensively throughout the southwest, I don’t know why it has taken so long for this plant to become available in the Panhandle, especially since it is cold hardy to Zone 5.
It is a bit slow to become established, and late in coming out in the springtime – have patience and place a marker so it’s not forgotten and weeded up. Note: Early spring-emerging plant may look similar to bindweed. It is best to plant this wild fuchsia in spring, rather than the fall. I noticed better success with quart to gallon size 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.
Desert marigolds are one of the prettiest desert flowers. The plant forms a neat compact rosette of finely cut silvery green leaves from which stems emerge topped with a bright golden daisy like flower. It is considered either an annual or short lived perennial. Scatter seeds from the spent plant to insure its return the next season. Over watering will doom this beautiful plant. Desert marigold can be seen blooming in the desert in winter and spring. In my garden, it's blooms begin in May and will continue sporadically into fall. Not awfully reliable in cold hardiness here.
Agastaches are some of the Southwest's showiest natives and one of our native perennials where must breeding and hybridization is being done. Native to slightly higher elevations that 3600 ft., it requires either afternoon shade or medium water-use. It has not been reliable in coming back for me, but it has for others. Well drained soil is a must. Nonetheless, it is easy to be seduced by its masses of blooms and alluring fragrances. Hummingbirds certainly are entranced.
Cypress vine is a native annual tropical vine of the Americas, but has naturalized in Florida and the Gulf Coast areas; said to be cold hardy to Zone 6. Fine lacy or thread-like leaves twine as it grows, putting on scarlet red flowers in summer. In addition to being a climber, it can be used as a groundcover.
White flowering zinnia is native to the Southwest and Northern Mexico. A low mounding plant, it becomes completely covered with small white flowers with a central yellow disk, similar to our native prairie zinnia, Zinnia grandiflora. Blooms from June through fall. Desert zinnia is toxic if ingested by humans.
New Mexican privet can be viewed either as a tall shrub or smaller tree. New Mexican privet will flower (tiny yellow) before leafing out with small oval glossy green leaves to be followed with black berries in the fall. Heat and drought tolerant will live in most soils and water-use areas. Attractive taller plant for the home landscape, similar to the yaupon holly in form.
Bush morning glory is a non-vining herbaceous perennial with a deep taproot, allowing it to be drought tolerant, but difficult to transplant. Arching branches with narrow upright green leaves emerge from the taproot. Summer blooming with 3 inch pink to purple funnel shaped flowers that open in the morning and close in the afternoon. Bush morning glory typically inhabits sandy and sandy loan plains, meadows, prairies and roadsides.
Herbaceous perennial. Fragrant hummingbird plant belonging to the mint family (Lamiaceae). Limited reseeding. Does better in afternoon shade. Locate in a transition area between medium and low water use. Leave plant and flower stalks standing in the fall, the plant does better trimmed back at the beginning of March.
Perennial from South Africa noted to be cold hardy for our area, but I’ve had mixed results, most years it didn’t winter over (although reported to be Zone 5). However, it will flower nicely the first year in the garden, so I’ve kept trying it. A Plant Select Plant for 2000. Perhaps it needs moister conditions in the winter than what I give it.
Echinacea angustifolia is the herbal echinacea. Native throughout most of the Midwest, and the Texas Panhandle. Very drought tolerant. It can be seen growing along roadsides and in nature generally. A good cut flower. The common name Black Samson refers to its roots. Not as showy as E. purpurea and newer introductions.
The most remarkable quality of Red Dragon Persicaria is its burgundy red patterned leaves and red stems, a plant grown much more for its foliage than flowers. (The flower stalk in the upper right is of Acanthus spinosus.) Not a native (native to China) it will come back if nipped by a late frost and will suffer sunburn in afternoon sun. Red Dragon may take 3 years before flowering, however, that is not a drawback.
Native perennial wildflower that will bloom periodically from spring into fall (presumably when there is adequate moisture). I have seen it many times in nature in the Texas Panhandle and West Texas. After the flowers have peaked, they do not fall off, but turn light and papery. They make a good dried flower. Reseeds!
This wildflower is toxic to sheep and possibly cattle. Humans should not eat any part of this plant. The flowers are fragrant and are attractive to bees, birds and butterflies.
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.
Sumacs are known for brillian fall foliage. Ground cover woody shrub 24-30" tall with dark shiny green leaves that turn a thrilling orange-red in the fall. Small yellow flowers at springtime.
Big Bend silverleaf is the most cold hardy of the Leucophyllums and has wintered over in Amarillo, Zone 7, for 5 years so far. Possibly cold hardy to Zone 6. It is hard to beat a more attractive summer blooming shrub for small xeric spaces. After summer rainfalls, Big Bend silverleaf, native to the Big Bend National Park area, becomes covered in silver blue flowers that twinkle like jewels among its silvery gray leaves. Hard to find, it's worth searching for.
Lantana urticoides (horrida) is a native perennial, and cold hardy for most of the state, except for areas in the Texas Panhandle. In the Panhandle, several species of Lantana are sold as summer bedding plants. Blooms prolifically summer and fall. Colors normally available are red, red and yellow, yellow, white and purple or mauve. In rare cases they may winter over. In areas south, lantana will grow into a shrub. The blue/black fruit clusters are poisonous.
Attracts butterflies.
Blue grama grass is a short, clumping warm season grass with thin blue green blades that is native throughout the Great Plains and Southwest. Able to grow in poor, dry soils, blue grama grass needs only about 12 inches of annual precipitation to survive. If seeded thick enough and with moderate irrigation, blue grama will form turf. Once establish, reduce to monthly supplemental irrigation, and mow not more frequently than monthly to a height of 4 inches. One advantage of blue grama over buffalograss is the speed of germination; it will germinate in 5-7 days.
Yaupon holly is a tall shrub or a small tree growing typically to 8-12 feet in the Texas Panhandle. Cold hardy to Zone 7 (still best to plant in a protected location), it prefers partial shade, especially afternoon shade. Low (once established) to high water use. Small leathery, glossy, evergreen, dark green leaves (to 1.5” long) have toothed margins on dense branching. Insignificant greenish white flowers in springtime followed by red berries in the fall. Female plants require a male plant to pollinate and bear fruit (dioecious). Attractive tall, traditional looking shrub.
Gayfeather is one of the High Plains jewels of autumn, sending up grasslike leaves or stalks that bloom gloriously in September and October to fuzzy purple spikes. At maturity, one plant can grow a dozen or more, size and number depending on rainfall amounts. Drier years, the stalks are few and short, but with monthly or twice a month watering, the plant displays much more vitality. The purple flowers contrast nicely with the many yellow flowers that bloom on the plains. Liatris punctata is the most drought tolerant of the genus.
Old fashion garden and English cottage garden herbaceous perennial that works well in the Southwest Cottage Garden. Hollyhocks are considered to be either a biennial or perennial. They produce copious seed but are not considered invasive or troublesome. Plant seed in the fall, or early spring. Avoid watering the foliage if irrigating, a drip system works better that above ground sprinklers.
A beautiful white variety of the purple coneflower. This picture doesn't do the flower justice.
Similar to the purple coneflower, this white variety is really a high water-use plant that appreciates afternoon shade. Deadhead to prolong the bloom period, but keep end of season blooms on for fall and winter interest.
I love ornamental grasses and this grass tops my list. Blueish green evergreen leaves. A cool season clump forming, medium height grass. Treat it as medium water-use for the first year or two. Blue avena grass is not particular about soil, just as long as it’s well drained. After 2-3 years, blue avena grass will put out light tan oat-like plumes. This grass performs better in afternoon shade.
Mock orange is one of those versatile old garden shrubs you can place almost anywhere; it will even flower in deep shade. Fragrant single pure white flowers in spring that may reoccur in the fall with a much lesser show. Drought tolerant once established. The versatility and fragrance must certainly be the reasons gardeners choose mock orange, it certainly isn’t for its irregular shape. I’m afraid I haven’t shown it much respect, allowing its mostly shady corner to be littered with gardener’s menagerie of plastic pots and unused brick-o-brack.
Pages
