What is the best time of the year to have my trees trimmed?

The ideal time to have your trees trimmed generally depends on the type of tree, its age, and specific conditions, but there are some widely recommended periods and important exceptions to keep in mind.

Here’s a breakdown of the best times for tree trimming:

• General Recommendation: Late Winter or Early Spring (Dormant Season)

  • Arborists generally agree that the best time to prune a tree is typically in the winter, after the tree has gone dormant. This period is usually from November through March.
  • Trimming during this dormant season helps enhance new growth when the weather warms up.
  • Visibility is better due to the lack of leaves, allowing for a clear view of the branch framework.
  • Proper wound closure is heightened in late winter before a spring growth spurt, which is crucial for preventing the spread of decay.
  • Pests and pathogens are less likely to enter trees through fresh cuts during colder months.
  • For deciduous trees (those that shed leaves annually), late fall to winter is ideal as they are dormant, and insects and diseases are less prevalent. This timing also helps avoid “bleeding” (sap flowing out of trees) that can occur if pruned in late winter just before spring.

• Specific Tree Types:

  • Young/New Trees: Generally, it’s best to wait a year after transplanting a new tree before significant pruning to allow the root system to develop and strengthen. Initially, only remove broken or damaged branches. Corrective pruning, such as removing double leaders or crossing branches, can be done. Gradual removal of lower limbs can happen over five to ten years as the tree stabilizes.
  • Subtropical Trees: These can typically be trimmed all year round due to their continuous growth and abundant sunshine and water. However, the industry standard suggests removing no more than 30% of live tissue in any season.
  • Flowering Trees: The timing depends on when they bloom:
    • Spring-blooming trees (which develop flowers on old wood) should be pruned immediately after they flower, typically in late spring to early summer. Examples include flowering cherries, crabapple, dogwood, and saucer magnolias.
    • Summer or fall blooming trees should be pruned in late winter or early spring before their dormancy ends. Examples include crape myrtles and American holly.
  • Fruit Trees: Pruning is usually best in late winter to early spring. While late July or August is an option, severe pruning then can weaken the tree. Late winter is generally preferred as early winter pruning can reduce the tree’s winter hardiness.

• When to Avoid Trimming:

  • Generally, late summer and early fall is the worst time to prune most trees. During this period, trees are preparing for dormancy and storing resources. Pruning can encourage new growth, which may prevent the tree from entering its natural dormancy and make it struggle to heal before cold weather, potentially leading to disease and decay.
  • Summer pruning is generally not recommended as most trees are actively growing, and trimming can discourage new growth for the next season.

• Emergency or Hazardous Situations: Any Time of Year

  • Dead, dying, diseased, or otherwise hazardous branches should be removed at any time of year. These pose a safety risk, potentially causing damage to your home, power lines, vehicles, or even injury.
  • Even if storm season has started, addressing obvious hazards can make a significant difference in preventing damage.
  • For oak trees, summer pruning can attract beetles that spread oak wilt, a serious disease. In warmer months, it’s better to stick to light, selective pruning for oaks and save structural work for the dormant season when disease risk is lower. Using a pruning sealer after pruning an oak tree can also be beneficial.

• Consulting Professionals:

  • While light pruning of small branches can be done by homeowners, anything involving large limbs, elevated cuts, or structural corrections should be left to a professional. Improper pruning can weaken a tree or even increase the risk of storm damage.
  • A professional ISA (International Society of Arboriculture) certified arborist can assess your trees, provide tailored recommendations, and ensure proper care for their health and longevity.