Main blooms primarily during the months of July (last half), August and September, sometimes into the first part of October.
Rudbeckia is advertised as heat and drought tolerant, but I have not found it so. I’ve found it to require at least weekly watering during the heat of the summer. A shortlived, southern native perennial, it likes the humidity and rain from southern climes. These very large and stunning composites may be worth your effort, just place within the correct hydrozone.
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.
It is so refreshing to see the rain lilies bloom after a long hot summer. Whenever they begin to bloom, I know the worst heat is over. Rain lilies are a delightful flower that sends up glossy green, grass-like leaves from its bulb in late spring. In mid to late summer, pure white flowers resembling a crocus open and continue through September, usually after a good summer rainfall. There are quite a few species and varieties (of various colors) of Zephrantes, however, Z. candida is the only rain lily cold hardy in Amarillo. I've grown it successfully since 2008.
Desert never equates with drab. The flowers on Desert Bird of Paradise are simply stunning! Though classified as a Zone 7 plant, I’ve grown Desert Bird of Paradise for 3-4 years near a south facing wall and have seen several others around Amarillo, without it dying back it to roots. However, if it does, just prune out the dead wood. Eye catching flowers bloom continually from June into fall and attract hummingbirds. Finely divided green leaves. It is said to survive on 8” of rainfall, but monthly soakings enhance it. C. mexicana, Mexican Bird of Paradise and C.
The flowers of Salvia darcyi are similar in appearance to Salvia greggii, however the shrub itself is more herbaceous than shrubby. I know of no common name for S. dacryi. Some sources say it is cold hardy to Zone 7, however it thrives in Denver Botanical Garden’s Zone 5. S. darcyi is native to the mountains of Northern Mexico and will do well in amended soil. Hummingbirds love it.
I have it planted in my xeristrip for a number of years. It will flower more vigorously with irrigation everyother week, when needed during hot drought years.
Texas red yucca is technically not a yucca, but has many of the same qualities as yuccas. Thick, succulent dark olive green leaves grow out of the base, as it is stemless. The coral red flowers appear at the top of a long raceme, often 4-6 feet tall. 'Yellow' and 'Red' blooming yuccas are also available. Although it's natural range is north eastern Mexico and West Texas, it is cold hardy throughout much of the Southwest. Allow for sharp drainage in moister climates to prevent root rot.
Lindheimers muhly grass is native to the Edwards Plateau of Texas. It is cold hardy and heat tolerant, a tall, warm season bunch grass. It forms a good size ornamental specimen with upright blue green or blue gray blades and tall showy, almost spike like inflorescences in late summer. Not as large as pampas grass, it is a better native alternative. There are two muhly grasses native to the Southwest, Muhlenbergia asperifolia, scratchgrass, and M.