Ask: As I drove down Main Street in Sebastopol last week, I was struck by the beauty of the stately trees with their many white blossoms that line the avenue. What kind of trees are these? Are they suitable for a residential landscape?
Answer: They admired crepe myrtles ( Lagerstroemia indica ), popular drought-tolerant street trees. Besides those in Sebastopol, you can see crape myrtles all over Sonoma County, from Sixth Street in Petaluma to the entrance of the Oakmont neighborhood and beyond. Crepe myrtles begin blooming in mid-July and continue to bloom through late September in a variety of colors, including white, pink, lavender, and red. In addition to the bright colors of the flowers, the bark of mature trees is also quite striking, with its mottled variations in tan, brown, cinnamon, and gray. While the trees you saw in Sebastopol have single trunks, other crape myrtles may have multi-branched trunks.
Crepe myrtles are native to temperate and tropical regions from Asia to Australia. Their leaf shape resembles that of a true myrtle ( myrtle ) and their colorful flowers are crumpled like crepe paper. The leaf colors can vary from green in summer to bronze, yellow, orange and red in autumn. Not only Lagerströmie Indica thrive in our hot summers and mild winters, but the colors of their long-lasting summer blooms and fall foliage are eye-catching from summer through early winter.
When crape myrtles bloom is the ideal time to choose exactly the flower color you want. Keep in mind that the plants are available as either multi-stemmed or single-stemmed specimens. Multi-stemmed trees are more shrub-like. As they mature, they develop a height and width that requires more space near the ground. The single-stemmed crape myrtle is a popular street tree that grows 15 to 25 feet tall and usually doesn’t interfere with power lines. If you’re short on space, consider a semi-dwarf variety that grows 4 to 10 feet tall. Crape myrtles can be susceptible to powdery mildew, so choose a resistant variety to minimize this problem.
They love full sun, well-drained soil
To maximize crape myrtle flowering, plant the trees in full sun and in well-drained soil to avoid waterlogging and stunted growth. Regular watering several times a week is necessary for the first 2 to 4 months after planting. During the first 1 to 2 years, a deep soaking to a depth of 6 inches once or twice a month is beneficial. Allow the soil to dry out between waterings. Crepe myrtles tolerate dry soil better than moist soil. Once established, they require less water. Keep in mind that clay soils, such as those typical of Sonoma County, retain water longer than the sandy, loamy soils more common in the western part of the county.
Although not essential, pruning maximizes flowering, improves shape, and stimulates new branch growth. Because crape myrtle flowers appear on new wood, stop pruning before April to allow new branches to grow. After careful pruning in the first few years, little further pruning is needed, aside from periodically removing dead or crossing branches, suckers around the base of the tree, and extremely long branches.
To improve water conservation, soil health and weed control, lay a 3 to 5 inch layer of mulch around your tree, leaving 3 to 6 inches of bare soil around the trunk. Mulch can also highlight the colors, shapes and textures of the crape myrtle flowers, leaves and bark.
You will find that the crape myrtle is not only attractive but also easy to care for, as it produces little waste for a deciduous tree and attracts few pests.
Contributors to this week’s column were Diane Judd, Patricia Decker and Karen Felker. The UC Master Gardener Program of Sonoma County https://sonomamgucanr.edu provides environmentally sound, science-based gardening information for home gardeners in Sonoma County. Send your gardening questions to [email protected]. You can find answers to your questions either in this newspaper or at our information desk. You can reach the information desk directly at 707565-2608 or [email protected].
