By David Jamar
Jones Park Forester
Although winter tree care usually isn’t a homeowner’s top priority, neglecting your tree now can lead to big problems in the future. As trees enter dormancy, cellular changes direct resources away from limbs and leaves to the roots, preparing the tree for growth during the warmer months. Proper winter maintenance – like watering, fertilization, and pruning – will help your tree flourish in the spring and stay healthy through the summer and fall.
Most established trees do not need supplemental watering during winter unless it’s unusually cold and dry. The amount of water a tree needs depends on the tree’s age, species, location, soil type, and weather conditions.
In general, evergreen trees will need more water than deciduous trees because they lose water through their leaves. If temperatures drop too low and the tree hasn’t received adequate water, the foliage on evergreens may die back from winter burn.
Deciduous trees require less water than evergreen trees because they have no foliage to remove water from the root zone. Overwatering young and newly planted deciduous trees during dormancy may lead to root rot and the death of the tree. If the winter is unusually dry or if temperatures are forecast to drop below freezing, supplemental watering is recommended.
Avoid using fertilizers high in nitrogen during the winter. These fertilizers may trigger new growth, which may be damaged as temperatures drop, causing dieback of limbs or stunted spring growth.
A well-balanced, slow-release fertilizer will not injure young trees when applied properly. Fertilizing young and newly planted trees during late fall or early winter can fuel root growth throughout the winter and spark new growth in the spring. For mature trees, fertilizer is not recommended unless a professional has diagnosed a deficiency in your soil.
Winter is also a great time for shaping both young and mature trees, especially deciduous trees. Not only are insects and diseases less prevalent but structural problems are more evident once leaves have fallen.
To shape the tree, identify your tree’s leader stem, which is the tree’s most vertical stem, and scaffold branches, which form the tree’s canopy. Once these have been identified, begin by removing crossing or crowded limbs and raise the canopy if needed. With proper pruning, young trees can develop a strong central stem and grow into a more stable form.
Want to learn more? Join Jones Park for its annual Arbor Day celebration on January 18 and 19. An arborist will be available to answer your tree care questions. Visitors can also help plant native trees at the park and take home a free sapling while supplies last.