A perennial plant is a plant that requires one or more years to reproduce and usually continues living, but not indefinitely. Whether a plant is cold hardy or not is not connected to being an annual, perennial or biennial.
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.
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.
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.
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.
Scabiosa columbaria ‘Butterfly Blue’, though first discovered in Ireland, will thrive very nicely in your transition zone as a border plant along turf, where it’ll receive medium to medium high water. Amend the soil well with organic matter for rich blooms and keep it deadheaded to prolong blooms. Afternoon shade is recommended. A little more trouble than usual, but well worth the softening effect this compact, mounded and cheery plant brings to the border; a Perennial Plant of the Year for 2000.
A Plant Select Plant for 2004, Pink Texas Skullcap has often been listed as a Zone 7 plant, but it is reliably cold hardy in Zone 6 and in protected Zone 5b sights. I’ve grown it in my xeristrip since 2000. Long blooming with no maintenance ever performed. These low growing, mounding skullcaps are excellent for Panhandle xeristrips and rock gardens. Native varieties are S. drummondii, and S. resinosa. The hybrid cultivar, S. x ‘Violet Cloud’, introduced by High Country Gardens, is an excellent violet skullcap as well as the natives.
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.
Golden current makes an attractive taller shrub at the edge of a lawn or vegetable garden, positioned to catch extra irrigation water. For three stunning weeks in spring it will be covered with tiny yellow flowers. I planted two in 2008, and have yet to notice the tasty berries, red currents, for which they are known. Quite cold hardy, if placed in full sun, it'll need twice a month watering to survive, or in half or more shade, once a month watering is sufficient. Multi stem shrub with small, rounded leaves with cut edges makes an attractive barrier or hedge plant.
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.
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.
An old world Mediterranean plant best known for the acanthus leaf shape used as a basis in classical Greek and Roman designs. The plant itself takes 2 – 3 years growth before flowering. Attractive flowers with purple bracts on tall spikes to 4’. Frost sensitive, will die back in a late spring frost, but will come back. Adds architectural and textural interest.
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.
Typically a Zone 8 plant, the Christmas holiday bulb, Amaryllis, has been successfully wintered over in Amarillo, specifically, the Wolflin area in this case. If you have a warmer, protected micro-niche, try planting your seasonal Amaryllis outdoors, and leave it there well mulched over winter. I 've winter over Amaryllis in my backyard, but it hasn't reliably bloomed. It requires a full sun location and well amended soil to soak up nutrients to be stored in the bulb.
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.
A new hybrid skullcap from High Country Gardens. A cross between two native skullcaps, Violet Cloud likes the soil lean and well drained. A sparkling addition for the rock garden, xeristrip and any low water-use area. Additional watering is required during establishment the first year, after that, it should be drought tolerant.
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.
Chamisa or rabbitbrush is a medium tall shrub with blue-green stems that produce clusters of golden yellow flowers from September throughout fall, very showy in the landscape. Matted hairs on thin leaves cast a silvery appearance. Native throughout the southwest, in warmer climates it is evergreen. The official name has been changed to Ericamera nauseosa, but is still referred to as Chrysothamnus (meaning golden bush). Seeds prolifically -- is a good pass-along plant to friends, neighbors, relatives and passersby.
You can't have just one. As soon as you plant one, you'll have a drift, then a sweep, then a field if you have the space. But I still don't consider the prairie coneflower to be invasive, merely pleasant. Next to the Indian Blanket, the Mexican Hat shouts Southwest prairies. And its a tough hombre. If your stand becomes too dense or too much, just weed some out. They're adaptable to most native soils and will thrive on available or once a month supplementation. Coneflowers bloom yellow, reddish or brown late spring into fall and make an attractive display when mixed.
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.
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.
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
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.