Are Crepe Myrtle Roots Invasive?
The crepe myrtle is a small tree, rarely growing taller than 30 feet (9 m.). Beloved by gardeners for its luxurious summer blossoms in shades of pink and white, the tree also offers exfoliating bark and an autumn foliage display. If you are thinking about planting one in the garden, don’t worry about the invasiveness of crepe myrtles and their roots. The crepe myrtle root system will not harm your foundation. The crepe myrtle root system can extend a considerable distance, but the roots are not aggressive. The roots are relatively weak and will not insert themselves into nearby foundations, sidewalks or endanger nearly plants. Crepe myrtle roots do not sink taproots deep into the ground or send lateral roots out to crack anything in their path. In fact, the entire crepe myrtle root system is shallow and fibrous, spreading out horizontally up to three times as far as the canopy is wide. On the other hand, it is wise to keep all trees at least 5 to 10 feet (2.5-3 m.) away from walkways and foundations. The crepe myrtle is no exception. In addition, the root system grows so close to the surface of the soil that you shouldn’t plant flowers in the area below the tree. Even grass might compete with the shallow crepe myrtle roots for water.
Do Crepe Myrtles Have Invasive Seeds?
Some experts list crepe myrtles as potentially invasive plants, but the invasiveness of crepe myrtle has nothing to do with the crepe myrtle tree roots. Rather, the tree reproduces so readily from its seeds that, once the seeds escape cultivation, the resulting trees can crowd out native plants in the wild. Since most of the popular crepe myrtle cultivars are hybrid and do not produce seeds, reproduction by seeds in the wild is not a problem. This means that you do not risk introducing an invasive species by planting a crepe myrtle in the backyard.