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.

Common Name: Black and Blue Sage, Anise scented sage

There are several varieties of Salvia guaranitica that range in shades of blue from light to dark. As with most of the tube-shaped salvia flowers, S. guaranitica is a hummingbird magnet.

Native to South America, S. guaranitica is not zoned cold hardy for the Texas Panhandle, but it has wintered over in protected Amarillo gardens in many locations for many years. It has wintered over for me at least 5 years, unprotected. Deadheading is not required.

Common Name: Woolly Creeping Speedwell

Low growing, drought tolerant evergreen groundcover that becomes covered in tiny sky blue flowers in early spring for about 6 weeks, then sporadically throughout the year. I’ve seen a few twinkling blue blooms in every month of the year. The tiny leaves of V. pectinata are gray-green and tomentose. Allow plenty of room for the spread of this fabulous groundcover; it’ll just keep going and going and going. And you won’t want it to stop. 

Common Name: Sundrops

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.

Common Name: Shadscale

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.

Common Name: Illinois Bundleflower

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.

Common Name: Gooseberryleaf globemallow, Current leaf globemallow

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.

Common Name: Mountain Mahogany

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.

Common Name: Gambel Oak

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.

Common Name: Texas Sacahuista, Texas Beargrass

Texas beargrass is a grass-like perennial evergreen plant native in rocky and limestone soils from central Texas to the upper Rio Grande Plains and west to the Trans-Pecos and into S.E. Arizona. Not a true grass, Texas sacahuista is a member of the lily (Liliaceae ) family. It flowers in Amarillo in early April. A short flowering stem barely rises above the many thin leaves. The flowers appear rose or reddish on the outside before opening,  are numerous, white to cream colored forming dense vertical clusters.

Common Name: Jupiter's Beard, Red Valerian

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.

Common Name: Blue Avena Grass, blue oat grass

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.

Common Name: Cascading Ornamental Oregano, Lebanese Oregano, Hop Oregano

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.

Common Name: May Night Meadow Sage

1997 Perennial Plant of the Year was chosen for it versatility in growing in many different regions of the US. And it will grow in our Panhandle gardens as well. Although reported to be drought tolerant once established, it does much better in a medium water-use environment with afternoon shade. When it is excessively hot and dry, it suffers from stress, but usually survive. Just give it a little more water when this happens.

Attractive to bees and butterflies. Seedlings may happily  appear in springtime. Native to Europe and Central Asia.

Common Name: Color Guard Yucca

There are numerous interesting yuccas to choose from besides the Yucca glauca or Y. angustifolia seen throughout our area. Y. filamentosa ‘Color Guard’ has some of the most striking variegation and will even flower in part shade, cold hardy to Zone 5. Other Y. filamentosa varieties to consider growing in our area are ‘Bright Edge’ and ‘Golden Sword’.

Common Name: Stansbury cliffrose

Previously known as Cowenia mexicana, it is known today as Purshia stansburyana, also, P. stansburyiana. It is still commonly called a cliffrose. The cliffrose blooms prolifically in May with creamy white to pale yellow fragrant flowers that continue blooming for several weeks. Semi evergreen, it loses it's leaves in colder winters. Upright stems and branches can appear unruly in its growth pattern; small dark green resinous leaves.

Common Name: Scarlet hedgenettle, Texas Betony

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.

Common Name: Snow on the Mountain

Snow on the Mountain is a showy plant native to the plains states. Heat and drought tolerant in the Texas Panhandle. Striking variegated green and white foliage, with small white summer flowers. Can be invasive and is toxic to humans, sap of plant may cause dermatitis. Deer resistant. Control spread by deadheading.

Common Name: Prince's Plume, Desert or golden Plume, Sentinel of the Plains

Elegant and stately desert perennial. Soft light blue green leaves. Stalks can tower above desert shrubs to 5-6 feet, but usually 2-4 feet, with racemes of yellow flowers similar to cleome or spider plant flowers in springtime. Requires excellent drainage and lean soils. Thrives on selenium rich soils. Native to canyonlands in SW U.S.

Common Name: Dwarf Ephedra

Ephedra minimus is a dwarf version of E. viridis. Woody base with many thin, branched evergreen stems. Rare to find in nurseries, it is appreciated for is evergreen presence and rarity. No leaves or flowers

Common Name: Shrub Live Oak, Holly Oak

Shrub live oak, often a medium size shrub, is native to the Southwest and the Texas Panhandle typically found in canyons, rocky cliffs and hillsides. Sometimes called a holly oak, the leaves are 3-4 inches long, spine-tipped and holly shaped bluish green leaves. It is prolific in putting out acorns. Cold hardy, heat and drought tolerant.

Common Name: Columbine

Many Aquilegia’s are native to the U.S. Golden columbine, Aquilegia chrysantha is a Texas and southwest native, has yellow flowers and can take more sun than some varieties. McKana's Giant is the hybrid columbine most often sold. Large beautiful bi-colored flowers dazzle in woodland and shady area. Rocky Mountain columbine, Aquelegia caerulea; and wild columbine, A. canadensis, are other common columbines. Rocky Mountain columbine is the state flower of Colorado.

Common Name: Sweet Autumn Clematis

Although usually sold as Clemantis paniculata, it could be C. terniflora. Sweetly fragrant, low water-use vigorous growing vine for great late summer display. Creamy white flowers form silvery seed heads.  Cut back in spring as it blooms on new growth.

Common Name: Hybrid Daylilies

Green sword-like foliage with striking bell or funnel shaped flowers that last only a day. Hundreds of different hybrids and cultivars in a wide range of colors, some early, mid and late summer blooming. Daylilies do better in medium, well-amended soil and a sunny location that enjoys afternoon shade, but they are versatile. Daylily leaves may exhibit alkalinity in clay soil. If this is the case, amend well with organic matter.

Common Name: Rock Rose, Rose Mallow Pavonia

Although there is question in my mind whether pavonia is a native in Texas, it’s been naturalized for a long time and is found growing in the Edwards Plateau and south Texas. Pavonia has been cold hardy for me for at least 5 – 6 years. Readily reseeds to the point of being a nuisance, but this is a minor annoyance.

Common Name: Plumosa, or Plum Meadow Sage

Unlike, S. nemorosa ‘May Night’, I don’t mind deadheading this salvia, perhaps because of its plum color it does not require as persistent deadheading. Notice the gray-green leaves of ‘Plumosa’, versus the green leaves of ‘May Night’. The stems tend to flop, but the flower stalks continue to grow and flower upright -- very strange.

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