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.
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".
Wagons Ho! Rugged, ragged and windblown -- a true picture of the western and southwestern landscape. If you have a skeleton of a steer's head, now is the time to use it, along with that wagon wheel. Sometimes referred to as the western sage.
Big sagebrush is a coarse, many-branched, aromatic, pale-grey shrub with yellow flowers and light silvery-grey foliage. It flowers in late summer to early fall. The leaves are wedge-shaped with three lobes.
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.
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.
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.
Virginia creeper, one of our pernicious native creepers, is a worthy low care vine for brilliant fall foliage and deep blue berries (highly toxic to humans) loved by birds. Virginia creeper normally spread by seeds in bird droppings, which is the method it came to my landscape. When spotted early, Virginia creeper easily pulls out, but if not spotted, within no time, it will cover a fence, climb a pole or cover an area. Which can be either a good thing or a bad thing, depending on one's view.
Alkali sacaton is a perennial warm season bunch grass native to the Southwest. In late summer to fall, airy triangular seed heads wave above the silver green grass blades. Grows in alkali soils, many say in locations where there is moisture nearby, prefering heavy clay soils. It is quite drought tolerant once established, and long lived. It will, of course, grow bigger or smaller depending on water resources.
Oregon grape holly is an evergreen holly-like shrub native to the Pacific Northwest Rockies down into California. Upright, it is slow growing but can reach a height of 8 feet. Best when grown in shade, especially out of afternoon sun. Prefers a more humusy soil but will only required once a month watering when established, however, can also be placed in medium and high water-use areas. Bright yellow flowers in spring, followed by dark blue berries in summer. The thick, glossy, holly-like leaves have spines at the points. Leaves turn from green to red in winter.
Daffodils are the most notable of the spring bulbs. Reliable from year to year, daffodils can be depended upon to bloom even when faced with late season blizzards and are unpalatable to deer and squirrels. Daffodils aren't too particular about soil, but do better in amended soil, planted about 4 inches deep in October to December. Typical bloom times are February through April, depending on the variety, and there are thousands of varieties to choose from.
Caladium corms 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. There are a over a thousand cultivars, most from the Caladium bicolor species. Plant bulbs after May 1st, only about 3 inch deep. Caladiums like it hot and moist. Complete shade works OK, or morning sun only.There are a few sun tolerant cultivars available. For larger leaves.
Sometimes referred to as Gaillardia x grandiflora ‘Burgundy’. A cross between G. aristata and G. puchella. I’ve not been able to determine whether these are 2 different varieties, or just name confusion. They must be quite similar, nonetheless. It reseeded once for me, so I'm not sure at all. Medium water for this plant through the heat of summer will prolong blooms, as will afternoon shade. A stunning plant and prolific bloomer for your border.
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.
This variety of cinquefoil has grown in my xeristrip for six years and flowers happily from late spring into fall, with moderate flowering during the heat of the summer. Will put on a new show of flowers after summer rain. It maintains a compact shape without pruning or any maintenance.
There are many other varieties of this wonderful North American native that grows throughout the Rocky Mountains. Other varieties require moderate watering. This variety was purchased from High Country Gardens; I have not seen this truly drought tolerant variety again.
Nandina is one of a few single species genera, a member of the barberry family (Berberidaceae). Though one species, several cultivars are available to add texture and interest to our low maintenance, low water-use landscape in either sun or shade. I plant mine in full shade, as there are few shrubs that will flower there. I personally favor protecting Nandina with afternoon shade, if planted in a sunny location.
Not our old fashioned garden zinnia. Zinnia grandiflora is the native zinnia for most of the Midwest, West and Southwestern parts of the United States. So widespread a wildflower, each region has named it theirs: plains zinnia, prairie zinnia, desert zinnia and Rocky Mountain zinnia. A terrific low growing and spreading groundcover for poor soils needing no supplement irrigation. Rugged! A survivor without being a pest!
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.
Agaves are striking and architectural Southwest native plants and are included in a group of plants I term Southwest evergreens. They are unusual in that at maturity, they only flower once, and then die. for this reason, some classify them as multiannual, rather than perennial. However, as they common name suggests, it takes many years before they flower. Leaves of the Agave are arranged in a spiral beginning from a near invisible stem, forming a rosette.Agaves vary in size from 4-6 inches to larger than man-size.
Maypop, or passion vine, is a perennial vine native to eastern and southern areas of the U.S. In the South, maypop grows into a woody vine, but in northern areas like the Texas Panhandle, it will die back to the ground. Lobed, dark green leaves, beautiful, unique flowers emerge in the summer to fall, producing edible fruit. Maypop will sucker, especially when ample watering is present. Passion vine, the most cold hardy of the genus, should be cold hardy to Zone 6.
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.
Lavender cotton, or gray santolina is a low mounding woody subshrub that should live on the lean side. Not that it won't overgrow if fed. It will maintain its compact shape in poorer soils without amending or fertilizing. Small silver gray leaves cover the shrub. Tiny yellow button flowers appear in summer. Evergreen, the santolinas are native to the Mediterranean area. Aromatic and edible, it's leaves were used as a flavoring in broths, sauces and grain dishes. Low water-use.
Mat daisy is a low growing spring blooming plant. Drought tolerant. Not exactly a groundcover, as the top growth disappears during summer and reemerges as a green basal rosette in fall, getting ready to bloom again in the spring. Blooms late March to May with small white daisy-like flowers that have pink undersides. Forms a compact ground-hugging mat. Will self seed some, but never invasively.
A native to Texas, flame acanthus loves the heat and full sun! A hummingbird and butterfly plant. Does well in poor soil. May only be cold hardy to Zone 7, however, it has come back for several years in the Panhandle. Grows rapidly and will flower the first year, if you must replant, this is still a good choice for mid to late summer and autumn flowers. Re-seeds some, transplant them early as their roots grow deep.There is another variety with light pumpkin colored flowers, but this one does not bloom as prolificly.
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.
Linum lewisii, the southwestern and western native perennial wildflower variety of flax was named after Meriwether Lewis, who was first to describe it during the Lewis and Clark Expedition. On July 18th, 1805, near the Great Falls of the Missouri Lewis recorded: "I have observed for several days a species of the flax growing in the river bottoms the leaf stem and pericarp of which resembles the common flax cultivated in the U'States. The stem rises to the hight of about 2 1/2 or 3 feet high; as many as 8 or ten of which proceeds from the same root.
Remarkable old Bourbon rose dating to 1868. Remarkable for fragrance and bright cerise pink flowers, and best of all, thornless canes -- it's people friendly! Not strictly a climber, but a mannerly climber.
Zephirin Drouhin is planted in a low water-use location.