Green as a flower color is usually a light tint of one of the hues of green.
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.
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.
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.
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.
Three leaf sumac is medium height woody shrub native to the Texas Panhandle and throughout the Southwest. Three distinctive cleft and lobed leaves (trifoliate) are medium to dark green. Small greenish yellow flowers in spring are followed by tart red berries in summer, which are used to make a lemonade-like drink. The shrub's flowers have a pleasant fragrance, even though it is called skunkbush by some. Beautiful golden and reddish fall foliage. Cold hardy to Zone 4, yet extremely heat and drought tolerant. Prefers sandy and well drained soils.