The winter damage to which trees and shrubs are susceptible often stems from their inability to draw water from the frozen earth. Although we don’t necessarily equate wintry conditions with desert conditions, the winter landscape in cold climates is, essentially, a desert, making plants susceptible to the "winter burn" I mentioned on Page 1. Properly watering the plants in fall, then, can be an effective means of minimizing injury to trees and shrubs during the winter.
Watering Plants in Autumn
- Try watering plants sparingly throughout early autumn, until the time when the leaves of the deciduous trees fall.
- In late autumn, after the deciduous trees have dropped their leaves, give both evergreen and deciduous trees and shrubs a deep watering.
Watering plants sparingly in early autumn will allow them to transition more smoothly from the growing season into the dormant season. Plants treated in this way will be less likely to put out new growth. At first glance, that may sound like a bad thing, but it's not. In fact, you don't want to see new growth at this point, because it will be tender and could well be damaged when winter arrives.
The dropping of the leaves on deciduous trees later in autumn is a convenient signal, a visual cue that it's time for watering plants to prepare them for winter. Trees and shrubs should be watered deeply at this time. Make sure to do so before the ground freezes, so water can reach the roots.
Watering plants properly in fall isn't the only "preventive medicine" to administer to trees and shrubs. Proper pruning can also go a long way toward winterizing them. And part of proper pruning is knowing when -- and when not -- to prune.
- Don't prune trees or evergreen shrubs in the early part of fall. Pruning at this time would encourage tender growth, which you don't want.
- If you need to prune trees or evergreen shrubs, wait till the latter part of the season, late winter or early spring. Look to remove weak branches that might otherwise snap in winter.
- Early-blooming deciduous shrubs are often pruned after they've finished flowering. Later bloomers are often pruned in early spring. Again look to remove weak branches that might otherwise snap in winter.
- Do you have tall trees near your house? If any of their branches are hanging over the house (thereby posing a safety hazard), have a professional come over to "limb" the trees. This is for the house's sake, not the trees'!
Other Wintertime Problems for Trees and Shrubs
- Animal pests
The burlap shelter mentioned earlier can serve to protect shrubs (and small trees) not only from wind, but also road-salt spray. In addition, the chicken wire (if buried a few inches below-ground) can serve to keep pests from nibbling at your plants. Avoid piling up mulch right around the base of a tree or shrub, as the mulch provides a hiding place for rodent pests, which might gnaw at the trunk. Keep the mulch at least one foot away from the base.
On Page 3 we'll consider how to winterize perennial flower beds....