A Flowering Plant That Likes Hot Weather

This 100-plus-degree heat has most of the flowering plants in my garden drooping and dropping their blooms as if to say, “Forget it; we’re shutting down.”  Goodbye columbine, farewell clematis, and so-long to a few roses and sage.  But there’s one heat-loving beauty that says, “Bring it on!”  Hello, crape myrtle.

While not native, crape myrtle blooms are a common sight in the foothills June through August.  A large bush that is often trained to a tree, crape myrtle flowers form in panicles reminiscent of lilacs, except that the petals are crinkly and look a little like crepe paper.  Flower colors range from the common hot pink to white, lavender, deep purple and red.

Brilliant blooms aren’t the only reason to love crape myrtles.  The tree form in particular is a true four-season star.  In late spring these mostly deciduous plants develop small, glossy green leaves.  Their mid- to late-summer bloom comes at a time when other flowering plants are fading.  Come fall, crape myrtles put on another show when the foliage turns bronze, orange or red.  Once a year, a new paper-thin layer of bark forms, then peels to reveal a smooth trunk with a mottled pattern of grey, cinnamon brown and cream.  I even like the show of peeling bark as it separates from the trunk.

Crape myrtles are not fussy about soil, and once established, are drought tolerant. (The California Department of Water Resources rates the crape myrtle as a “low water use” tree.)  As long as they get the heat and sun they need and aren’t over-watered or over-fertilized, crape myrtles are not particularly bothered by pests or diseases.  The one exception is their susceptibility to mildew in humid climates.

The crape myrtle’s natural growth pattern is as a dense, round, multi-trunked bush that you can keep trimmed to a hedge.  Because the trunks are so attractive, they also make splendid trees. They can eventually reach 25 to 30 feet tall and wide, but there are many smaller varieties.  Most crape myrtle trees sold in nurseries have been trained to just one trunk (I have a few of those), but I’ve seen photos of mature trees trained to three to five trunks, and they’re beautiful.  You can create such a tree over time by buying a bush and then selecting however many branches you’d like to keep to form its structure.

Because crape myrtles grow at a moderate pace, it’s relatively easy to shape them as you please over time, as long as you do it judiciously.  The rule of thumb is to trim the tree no more than 12 to 18 inches in winter or earliest spring.  Crape myrtles bloom on new wood, so be sure to prune before new growth forms.

Crape myrtles (genus Lagerstromia) are native to Southeast Asia, China and Japan. The common crape myrtle (L. indica) from China and Korea was introduced circa 1790 to Charleston, South Carolina by the French botanist André Michaux.  In the 1950s, the director of the U.S. National Arboretum, John Creech, crossed seedlings from L. indica with the Japanese L. fauriei, and from that beginning came many hybrids with Native American names like “Natchez,” “Hopi,” “Comanche” and “Zuni.”  These are the most common crape myrtles found in nurseries today. Pair them with other plants that thrive on hot, dry weather and infrequent but deep watering:  lavender, salvia, rockrose, rosemary and most foothills natives.

The blast-furnace heat of summer is the only time I whine about the weather.  Thank goodness there are color wonders like the crape myrtle to keep my spirits up and my water bill low.

Rachel Oppedahl is a University of California Cooperative Extension Master Gardener of Tuolumne County.

Note: When infested by aphids crepe myrtle and other trees will have a sticky substance on their leaves and the ground under them. It is called honeydew secreted by aphids and other insects as they feed on the plant’s sap. Lady bugs, horticultural oils, and other methods can help prevent an infestation.