If you're looking for flamboyant color come summer, this is your year to turn to hibiscus. They're tropical. They're temperate. They're totally tremendous. Some options:
Tropical hibiscus The iconic member of the entire clan, this state flower of Hawaii (the yellow hibiscus) comes in a wide assortment of shades of red, pink, yellow, orange and white, many with two and three colors per flower. Many are single-flowering (5 petals), while others are fully double (many petals). All have glossy, dark green leaves that are evergreen in frost-free settings. That means you'll either have to lose your plants the night of the first freeze or grow them in pots, so that you can bring them inside.
As with most members of the hibiscus clan, tropical hibiscus flowers last only one day. The plants produce buds and flowers on new growth. Their new buds will continue to develop as long as you keep the plants consistently moist and well nourished with a water-soluble, high-nitrogen fertilizer. They require almost full sunlight, although a little protection from the midafternoon sun in midsummer may slow down their likelihood of wilting. Hibiscus plants of all types abort unopened flower buds when they are allowed to get even modestly too dry.
Tropical hibiscus grow quite well in pots, although you'll certainly want to repot your plants once or twice annually, to keep them growing at peak vigor. Use a loose, highly organic potting soil each time that you step up your plants. Should they eventually outgrow the space you have for them, you can use air layering to propagate new plants.
Hardy hibiscus These are Texas-tough perennial plants that can handle outdoor temperatures to 20 below and colder. Their leaves are large and coarse-textured.
Hardy hibiscus plants establish as clumps of many stalks that grow to 3 to 5 feet tall. Unlike tropical hibiscus, the hardy types' stems do not produce branches. Flowers are borne for several months at the tips of the stalks, often two or three blooms per stem per day. That's especially notable when you consider that the flowers may be as large as dinner plates. Flower colors include shades of red, pink and white, and the blooms are always single. Due to their dominant look, use hardy hibiscus toward the back of your floral border.
Rose-of-Sharon, or althaea If you'd prefer something of a more permanent landscaping shrub, this is your sister. Depending on the variety, althaeas range in mature height and spread from 10 to 15 feet. They're winter-hardy clear to the Upper Midwest, so our tame Texas winters are no challenge at all. Flower colors include red, pink, white and lavender. Some types have double blooms, while others are single. Many have contrasting "eyes" in the centers of the blooms.
Roses-of-Sharon, if the truth were known, aren't too thrilled with hot, dry Texas summers. The plants produce quantities of buds in May, but in bad-weather years of heat and drought, they may drop half or more of those buds before they open. Mulching and deep soakings both help.
Turk's cap This is a hibiscus cousin of a different turn. Its flowers are spiraled, like rolled sheets of red paper. They never really open, but that doesn't slow down the hummingbirds. They're attracted to Turk's cap like teenagers to pizza. And, another difference: Turk's cap grows and blooms well in partial to fairly heavy shade. You'll even find it native to the East Texas woodlands.
Turk's cap dies to the ground with the first hard freeze, but the clumps re-emerge each spring, getting bigger and fuller each year. By summer, the blooming has started, and it will continue right up to frost. The plants grow to 4 to 5 feet tall and wide, although a more compact form is also sold. You'll occasionally see pink- and white-flowering forms. A variegated type offers interesting foliage.
Neil Sperry publishes Gardens magazine and hosts Texas Gardening 8-11 a.m. Sundays on WBAP AM/FM. Reach him during those hours at 800-288-9227 or 214-787-1820.