Plant Answers

Weekly Express-News Article
By Calvin R. Finch, PhD, SAWS Water Resources Director, and Horticulturist
Saturday, July 7, 2007

“Hot Weather All Stars”

It has been a wonderfully cool spring and early summer, but the hot weather is here. The hot weather cuts down the gardening opportunities, but there are some all star performers that will do their best show during the blistering heat. They are blooming in area landscapes and can also be planted at this time of the year. Consider esperanza, poinciana, firebush and rock rose for summer blooms.

Esperanza is also called Texas Bells. The blooms are bright yellow and look like miniature bells (1/2 dollar size). The foliage is light green. Most winters esperanza freezes back to the ground. If the weather is mild and they do not freeze back the plant eventually makes a small tree. There are several 15 foot esperanzas downtown and near the Riverwalk where it rarely freezes. If you cut them back to the ground each year they grow to seven feet most summers. Esperanza have really become popular since the “Gold Star” selection was introduced by Jerry Parsons. They are blooming machines. The older selections had a few blooms at the end of the stems. ‘Gold Star’ begins blooming when it is two feet tall and has large clumps of flowers throughout the plant. Esperanza benefits by being deadheaded as the current flowers decline. If the spent flowers are not cut off, seed pods form and there is more time between flushes of blooms.

Esperanza are not eaten by deer and are good nectar sources for hummingbirds. They require full sun and like hot weather. This year they did not start blooming until the end of May because of the cool weather. Last year they began blooming in April and bloomed into December.

Pride of Barbados (also called poinciana) like the sun and heat as much as esperanza. Like esperanza they do not need supplementary irrigation and they are a favorite hummingbird plant. Butterflies also favor the rounded clumps of “glow in the dark” orange and yellow blooms. Unfortunately deer eat poinciana. A poinciana makes an airy tropical looking plant that freezes back each winter, but grows to seven or eight feet tall by summer’s end.

Firebush is a sun loving summer bloomer in the same league as poinciana and esperanza. It has nickel size tubular red blooms that cover the shrub from June until November. Firebush has an attractive red tint to its foliage and purple red foliage after the first cold wave moves through. In between the red blooms is probably the most favored hummingbird plant in the garden. If you plant one in a 3-5 gallon container on the patio the plant will grow to 2.5 feet tall and wide. The toughest hummingbird in the neighborhood will take possession of the firebush. During fall migration that is usually a male rufous hummingbird.

In the garden the firebush will grow to at least six feet every summer and die back to the roots in the winter. In native soil they are very drought-tolerant, but in a container they require more frequent watering, even more than hibiscus.

The firebush is a disciplined growing plant, the fourth “All Star”, ‘Indigo Spires’ Salvia is far from disciplined. At the Botanical Garden ‘Indigo Spires’ grows to six feet tall and sprawls in all directions. It achieves “All Star” status because of its drought-tolerance, pest free growth and blue blooms. The dark blue blooms make a spectacular show. Deer do not eat salvia and they are a favorite nectar source for butterflies and humingbirds. ‘Indigo Spires’ freezes back to the ground every winter.

Pavonia is also called rock rose. The blooms are quarter size, flat and pink. Its growing pattern is best described as “old fashioned.” Rock rose sprawls outward from its base for five feet. On some sites it grows over three feet tall. It makes a good informal ground cover for sunny dry sites. Pavonia is a favorite butterfly food source.