White, silvery or cream in color.
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.
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.
Desert globemallow is one of those native plants that keeps on giving, asking so little in return and is a worthy addition to any native or xeric garden. Typically, desert globemallow sports pretty pink flowers. though some plants will bloom white, coral or lavender. Whatever color, they are worth the addition to your sunny and dry landscape for their pleasant cheery nature. Similar to appearane to S. coccinea, a coral blooming species.
Giant sacaton is one of the largest bunch grasses native to the Southwest, like alkali sacaton on steroids. Seems to thrive in poor soils with no supplemental irrigation. It will grow even bigger with added moisture. Thick textured grass blades, it will rival pampas grass for size and beauty, although it plumes are near as showy, giant sacaton has a flowing fountain appearance. A warm season grass, it is cold hardy and thrives in sun and heat.
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.
A good drought tolerant ground cover for use in a border, in a xeristrip or a rock garden. Evergreen grayish green leaves with fine hairs (tomentose). Will grow too tall and gangling in too rich and moist a soil. Some areas of the country have noted Cerastium tomentosum to be invasive, but I have not seen those tendencies here. A good substitute for the annual alyssium. Cerastium tomentosum var. columnae is a commonly available variety.
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.
Dasylirion is one of the plants I call a southwest evergreen. Different in appearance from traditional evergreen shrubs, it fulfills the same purpose in native and xeric landscapes. Symmetrical rosette of narrow leaf blades or leaves emanating from the center of the rosette. Barbs lining the margins of the thick pale green leaves give Dasylirion another common name, sawtooth yucca. As Sotol ages, a trunk may form under the rosette and even multiple heads may develop. At maturity, an 8-10 foot tall flower spike ascends from the center where thousands of small creamy white flowers open.
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.
This native shrub should be used alot more in our area. Drought tolerant shrub. If planted in a moister area it is important to have good drainage. Attractive and pleasantly fragrant fern-like foliage. The tiny white flowers with yellow centers that appear towards the end of the branches in June should be clipped in fall to late winter for better appearance. It is said the deer do not browse fernbush. Semi evergreen, it does loose its leaves in Amarillo. Reputed to be cold hardy to -25°.
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.
Summer flowering low water-use native tree, several varieties to choose from. Willow like green leaves. Cold hardy reliably in Zone 7, will winter over most years in Zone 6. The variety pictured in the close-up flower photo is "Lucrecia Hamilton", the variety in the third photo is 'Art's Seedless'. During early autumn snows, be quick to shake snow off the branches to avoid breakage.
Cliff fendlerbush is another Texas and Southwest native shrub too little used in the xeric landscape. Springtime lifts the cliff fendlerbush above the ordinary into prominence in the landscape. It is said the ravines and arroyos look dotted with snow from a distance, so profuse are the fragrant, creamy white, sometimes with a pink tinge, four petaled flowers in May and June. It's natural element is rocky arroyos (rupicola=rock dweller), cliff ledges and limestone soils with good drainage that average 12-18 inches of moisture with hot sunny days.
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.
Another old garden perennial that’s still good for our Panhandle cottage gardens, Physotegia virginiana is native to eastern and southeastern US. A terrific addition to the late summer and fall garden. Comes in three pleasing colors of light pink, purplish pink and a real pretty white. The white variety "Miss Manners' and 'Summer Snow' are both better mannered, not spreading quite as vigorously. It's native habitat is in moist, rich soils, but keeping it on the lean side makes it more "obedient".
The Arizona rosewood is classified either as a quite tall shrub or short to mid height tree. One of it's best features is that it is evergreen, with slender glossy green leaves approximately 3 inches long. It puts on small white flowers in summer. One of the few drought tolerant, native, evergreen trees available in the trade. Slow growing.
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.
The old fashioned larkspur is a drought tolerant reseeding annual, previously associated with delphiniums (now in the Ranunculaceae family). I’ve grown it in my alley, in the xeristrip, and its crept into my medium water-use zone. Deadheading keeps millions of tiny seeds from overcoming your garden next year, and also keeps the blooms coming. Larkspur can flower for six weeks. Again, deadheading is important to prevent a massive infestation throughout your landscape.
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.
Arizona rosewood is one of the few native evergreen trees or tall shrubs that are low water-use. Underused in the Texas Panhandle, mostly due to lack of availability. But with searching in Albuquerque or Santa Fe, one should be able to locate a specimen. Faster growing than the Chisos rosewood. Long slender, serrated, glossy green leaves with white flowers in summer.
Winterfat, formerly Ceratoides lanata, is a drought and heat tolerant that normally is found in poor, alkaline soils throughout the Southwest in grasslands and scrublands. Winterfat is a low rounded woody shrub with pale blue green to gray leaves. The distinctive characteristic is the long wooly seed stalk it puts up in the summer. Towards winter, the stalk appears to be covered with wool.
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.
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.
Not all succulents are cacti, nearly all cacti are succulents (a few exceptions). Nearly all cactus species are native to the Americas, providing a prickly evergreen presence. There are many cactus that are cold hardy for the Texas Panhandle. There might be one for your garden.
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.