Plants with Winter Damage
Faced with a yard full of damaged plants after a hard winter, often the first impulse of the gardener or homeowner is to start pruning, removing and replacing. Sometimes patience is needed in order to give plants time to recover before deciding on the best course of action. First, let’s discuss some of the causes of winter damage.
In winter, trees and shrubs that are evergreen, lose water by transpiration. This loss is greatest during periods of strong winds and on bright sunny days, because it is harder for plants to take up water when the soil is cold or frozen. Desiccation, which is the removal of all moisture, occurs when water is leaving the plant foliage faster than the roots can replenish it. Most severe damage is seen as discolored, burned looking needles or leaves. The foliage of some evergreen shrubs may even turn yellow or orange.
Not only can leaves show winter damage, branches can become dehydrated and die. The damage is usually the worst on the side of the plant facing the wind or sun or near a reflective surface which can be the side of a light-colored house, concrete, or snow. Any plant that is still alive will attempt to recover from freeze damage. The threshold of absolute damage (death) is different individually and of course for each species.
During especially hard winters, plants that have borderline hardiness will suffer the most, and may even die. Since the Asheville area’s winter was particularly harsh this year, the possibility has increased that many trees, shrubs and perennials that performed well in previous years will have suffered a significant amount of damage because they are not hardy down to the negative temperatures we experienced.
Be assured that many plants that look dead will begin to recover when the weather warms up. The extent of damage will not be apparent until re-growth starts. While initial damage estimates can be made by observing foliage and stem tissue, many plants are still in the process of realizing damage inflicted by the cold weather. In some cases, root systems or circulatory damage is not yet apparent. There are often no outward signs until heat or other stress causes the plant to collapse. What this means to you is that pruning should be delayed in all cases where frost damage is apparent, including discoloration. When growth resumes in the spring, you will easily see which stems or branches are not recovering fully.
The method of recovery and resulting appearance will not always match our idea of how the plant should look or behave in our gardens. Many plants will have lost all their woody parts, but will begin to re-grow from root or stem tissue. This is a normal and typical recovery process for the plant. However, the temporary appearance of the landscape may not be acceptable to some gardeners. This means that each site will have to be evaluated. Do you let the plants recover in their own way or time or replace them with already vigorously growing and pleasingly shaped specimens? On going evaluation is necessary to assess which plants will recover in time and which ones should be replaced.
Snow Creek Landscaping is a full service landscape company located in Arden, NC. If you need help with winter damaged plants, give us a call at 828.687.1677 or visit www.snowcreekinc.com.
Sources: http://www.ces.ncsu.edu/depts/hort/consumer/weather/coldprotect-shrubs.html
http://www.starnursery.com/110-taking-care-of-frost-damaged-yards