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.
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.
Elephand ears are plants grown from corms (called bulbs, but not true bulbs), with large leaves on upright stems. Colocasia leaves point downward (Alocasia leaves point upward). Colocasia gigantum and C. esculenta are two species most often used. These plants are grown primarily for their foliage and prominant veining, rather than flowers. The flowers are typical aroid type with a white to yellow or light green spathe, and may not even flower in shorter growing seasons.
Distinctive flat, thin upright leaves with flowers arising from the stem.
‘Red Rocks’ is another hybrid cultivar, named for the Denver, Colorado red sandstone area and amphitheater. P. 'Red Rocks' is highly suitable for the average garden, rather than a specialized penstemon bed. Again, do not deadhead unless reblooming has occurred and you desire a tidier appearance. Don’t over water or over amend the soil, but it will thrive companionably with other medium water-use plants.
Exciting drought tolerant groundcover! This gray-green leaved, evergreen groundcover adds quite a sparkle to any xeristrip or low water-use bed, border and rock garden. For prolonged summer blooms, water monthly during the growing season. Needs full exposure to sun and little water. Like's it's soil lean.
Delightfully fragrant with a sweet honeysuckle scent. A truly beautiful addition to any xeric bed or border.
Sedum, ‘Autumn Joy’ is one of those foolproof additions to your autumn garden, so aptly named; for the joy it brings to the autumn garden. Easily propagated by stem cuttings or root division. As with most sedums, afternoon shade helps. Grasshoppers have nibbled at its leaves in early summer without stunting the plant’s flowering ability.
Most notable in the meadows and fields of California, the California poppy grows throughout the southwest. Considered to be both annual and perennial, it either comes back the next year or it reseeds. Once you have a stand established, it should continue in your landscape, but not invasively so. This past summer of 2012, my California poppies bloomed in both the spring and our unusual fall. Blooms in April and May. Finely cut blue-green foliage make an attract plant outside the bloom period. The foliage should die back in summer.
Santa Fe phlox is rarely available even at native plant nurseries, but when it is, don't pass it up. Sun loving and drought tolerant, the Santa Fe phlox blooms late spring throughout the summer with once a month watering. Five petaled, small pink flowers about an inch across with a small white eye can cover the plant. Native to canyons, mesas, and rocky desert slopes from West Texas to southeastern Arizona and into northern Mexico. Seeds of the phlox pop out when they are mature, making seed collection and propagation difficult.
Broom snakeweed is a small mounded subshrub with yellow greenish thread-like leaves, native throughout the Southwest and western half of the North American continent. In the fall, it becomes covered in small golden yellow flowers. Bees and nectar butterflies are attracted to it in numbers. Usually grows to only a foot tall.
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.
Artemisia versicolor 'Sea Foam' is mostly grown for its gray foliage. To keep it's desired compact shape, cut off flower stalks after blooming, which is its only maintenance. Soft, rubber-like feel to its short, clustered, needle-like appearance on short 1 inch wide columns. It gives the impression of a coral bed in your rock garden. Not invasive. 2004 Plant Select Plant.
Delicate fern like foliage for your shaded woodland areas. Will grow in a low water-use zone, however, the foliage will disappear in summer. Delicate tubular, yellow. White and blue varieties have been available locally. An excellent choice for underplanting trees, especially for a medium water-use zone. Will reseed.
Grown in the South for decades, most people think of crape myrtle as a native American plant; it is however native to China and Japan. Small tree or large shrub that is cold hardy to Zone 7. I’ve grown the same crape myrtles for over 20 years, but they’re planted close (too close!) to my bricked house on both the northeast and northwest corners. They’ve been stem hardy, not just root hardy, and have grown up to about 10-12’. In most cases, crape myrtle will not grow into tree form in the Panhandle, but there are mature, tree size crape myrtles in Amarillo.
A long-lived evergreen penstemon for the average bed or border. Small orange red tubular flowers attract hummingbirds, as do most red tubular flowers. Low growing and longer flowering than most, especially the more mature the specimen.
After several years, the pine needle like foliage can resemble a miniature bonsai. Pineleaf penstemon is also a must-have for the low water-use bed or border or rock garden because of its evergreen foliage and longer blooming nature. In late summer, snip off the dried, spent flower heads; some re-blooming may occur.
Most gardeners’ acquaintance with veronicas is with the Veronica spicatas, ‘Red Fox’, ‘Icicle’, and ‘Sunny Border Blue’; the tall, spiky red, white and blue medium and high water-use veronicas. But consider the low water-use option, V. incana. Deadhead to prolong the blooms and water deeply once a month, once established in well-drained soil. The gray-green leaves should be a give-away by now as to its water requirements.
Veronica x ‘Blue Reflection’ should be an indispensable evergreen groundcover for you, as it has become for me.
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.
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.
Two southern native hibiscus suitable for the medium to high water-use garden. Large green leaves are superseeded by very large and showy flowers. H. moscheutos is cold hardy and has some of the largest flowers, up to a foot across in red, rose and white, usually with a red eye. H. coccineus blooms scarlet 3 inch flowers -- not cold hardy but worth trying as a specimen container plant.
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.
Native herbaceous perennial to the central and eastern U.S.; will grow in a variety of soils, including poor soils. False blue indigo did not flower the first year. Flowering improves as the plant matures. The foliage may go dormant and disappear towards the end of summer. Baptisias belong to the pea family (Fabaceae), a legume. Flowers are similar to a lupine. Other species colors are white (B. alba) yellow (B. sphaerocarpa), and other variations and cultivars, including 'Chocolate Chip', which features a light reddish brown flower, similar to milk chocolate.