Crepe myrtles, known for their abundant and vibrant summer blooms, are a favored sight in many landscapes. These deciduous trees, scientifically classified as Lagerstroemia, offer a long season of color, smooth bark, and attractive fall foliage. While generally resilient, providing appropriate winter care helps ensure their continued health and a spectacular display of flowers in the warmer months.
Preparing for Winter Dormancy
Preparing your crepe myrtle for winter dormancy is important. Deep watering in late fall ensures the soil is hydrated before freezing temperatures, helping roots withstand drier winter conditions, especially in areas with limited winter precipitation.
Applying a 2 to 3-inch layer of organic mulch, such as shredded bark or leaves, around the base of the tree, extending to the drip line, insulates the root system. This helps regulate soil temperature, retain moisture, and contributes nutrients as it decomposes. Avoid piling mulch directly against the trunk to prevent rot. Do not fertilize crepe myrtles after late August, as this can encourage new growth susceptible to frost damage.
Winter Pruning Practices
Late winter or early spring, before new growth emerges, is the optimal time for pruning crepe myrtles. Pruning during this dormant period allows for clear visibility of the leafless branch structure. The primary goals include maintaining the plant’s natural shape, improving air circulation, and removing dead, diseased, or crossing branches.
Avoid “crepe murder,” which involves severe topping or cutting branches to thick stubs. This practice weakens the plant, making it more susceptible to pests and diseases, and disrupts its natural form. Instead, focus on selective thinning, removing lower limbs thinner than a pencil’s diameter and any branches growing inward. Make clean cuts just above an outward-facing bud, to another branch, or at the branch collar, the swollen area where a branch joins the trunk. This approach promotes healthy growth and preserves the tree’s beauty.
Protecting Young or Tender Crepe Myrtles
Young or newly planted crepe myrtles, or varieties with less cold hardiness, require additional winter protection. While established, mature plants in USDA hardiness zones 7 through 9 withstand winter without extensive intervention, vulnerable specimens need specific measures.
Protection techniques include wrapping the lower trunk with burlap or a frost cloth to shield the bark from freezing temperatures and harsh winds. For young plants, wrapping branches with burlap and adding insulating filler like straw or leaves helps. Container-grown crepe myrtles are more vulnerable as their roots lack insulation; move them to a sheltered location like a garage or basement if possible, or insulate their pots with burlap or bubble wrap.
Common Winter Issues and Solutions
Even with proper preparation, crepe myrtles can experience winter issues. Damage appears as stunted leaf development, branch dieback, or a lack of new growth in spring. This can occur due to extreme cold, winter desiccation (drying out), or unseasonably warm spells followed by hard freezes that cause premature dormancy break.
If branches appear dead or do not leaf out, gently scrape the bark; green underneath indicates viability, while a brown interior means dead wood. Crepe myrtles can recover from winter damage, often by producing new shoots from the crown even if upper branches die back. Wait until late spring or early summer, around late June or early July, to assess the full extent of damage and prune back to where new growth is evident. This allows the plant to sprout new foliage before removing damaged sections.