Crepe myrtles and winter damage

-A A +A
By Jeneen Wiche

In 2010, I wrote “we should use more crepe myrtles in Kentuckiana, they are not just for warm, temperate climes; in fact, there are a great many that go unbothered by an average winter in our parts.”

Well, famous last words, right? I guess the operative words are “average winter.”

Crepe myrtles are one of the last of the summer blooming shrubs to break dormancy in the spring. In fact, many fear that their crepe myrtles are dead because they are so slow to leaf out. This year it just might be the case, however.

Winter die-back is not a total loss because the plant will come back from the root system if there is die-back on old wood; and they do bloom on new growth, so you will still get high summer bloom in July and August. But the downside to losing the woody part is that we also lose the age of the wood, if you will. The peeling bark that is one of the attributes of crepe myrtle usually doesn’t happen unless there is at least five years of age on the wood, so it is important to select hardy varieties in order to enjoy the exfoliating bark. Also, the old varieties suffer from powdery mildew, a problem that was solved when the National Arboretum started their hybridizing work with crepe myrtles.

Back in the 1960s, Dr. Don Egolf at the National Arboretum in Washington, D.C., began work on hybridizing crepe myrtles in an effort to improve hardiness, mildew resistance and overall garden appeal. He crossed Lagerstroemia indica, with its great blooms, and L. fauriei, with its winter hardiness and powdery mildew resistance, and came up with a great hybrid crepe myrtle for people in zone 6. The hybrids that Dr. Egolf developed and the ones that continue to come out of the National Arboretum have been named after American Indian tribes. Some of the ones to look for include Natchez, which can reach 15 feet. Natchez has white blooms and exceptional exfoliating bark. Others recommended for exceptional bark are Apalachee, Lipan, Osage, Biloxi and Kiowa.

We have had some of the National Arboretum crepe myrtles at the farm for years and I can attest to their hardiness. Acoma has come back from old wood for over 25 years. The last two winters have been hard on the shrub, however, with some spotty die-back. Although, interestingly enough, the “Watermelon” crepe myrtle planted in the cluster was killed to the ground. It is not one of the National Arboretum hybrids.

Some newer introductions out of the Arboretum include some dwarf hybrids that stay really small, like the miniature Pocomoke and some long-awaited red blooming crape myrtles. In 2003 Arapaho and Cheyenne became available. Arapaho will reach about 15 feet at maturity; Cheyenne is a bit more compact and rounded in habit. Hopi stays on the mall side, with lavender blooms.

They really aren’t picky plants, but full sun is ideal for maximum bloom and a tighter growth habit. I recommend removing leafy growth from the base so you can better enjoy the bark. Be patient in the spring, because it has been my experience that crepe myrtles are slow to break dormancy. Be patient, and if you have a National Arboretum hybrid, chances are the plant will come through the winter unscathed.

Don’t give up on Lagerstroemia indica, the common crepe myrtle. Many of the old crepe myrtles that are in Kentuckiana landscapes are root hardy but are killed back to the ground from time to time. Every decade or so we have one of those winters where we experience prolonged bouts of below freezing temperature, something the plants cannot withstand. But most plantings are in a microclimate (i.e. protected area or on south side of house) that keeps them safe.