We had been spoiled this winter. Until now, we have had a pretty ‘calm’ winter in Central Nebraska. This past week we were reminded of what a normal winters in Nebraska feels like. Sustained winds and subzero temperatures weren’t just hard on us, they were also hard on our landscape. Find out what to be on the lookout for come spring and what you can do now to help the landscape yet this winter.
The warm and windy weather with little snow cover is increasing the chance for winter desiccation in cool-season turf, trees, and shrubs. Desiccation occurs when the roots cannot supply enough water to the dormant or semi-dormant plant to keep up with the amount of water lost through the leaves and crown. The recent warm temperatures increase evaporation from the plant and soil surface, and the water loss is magnified by the high winds. Desiccation injury is most noticeable on exposed or elevated sites, especially those with high sand concentration.
Trees and shrubs can suffer from winter desiccation. Woody plants with shallow root systems are usually the hardest hit. Spruce, fir, pine, arborvitae, yew, Oregon grape-holly (Mahonia), holly, and boxwood are some of the more common evergreen plants that would benefit from supplemental winter irrigation during extended dry seasons.
There are a few steps that you can take to prevent winter desiccation in trees and shrubs. Providing supplemental water this winter can help to prevent desiccation damage. There are some rules to providing supplemental irrigation in the winter. Water should only be applied when the daytime air temperatures are above 40 degrees F. Try to apply the water in the middle of the day and allow it plenty of time to soak into the soil profile before the temperatures drop below freezing. If it is not given ample time to soak in, there could be a resulting layer of ice on the soil’s surface that could cause some damaging effects on the trees roots and possibly surrounding turf.
Winter desiccation injury can also happen to turfgrass. It is common in Nebraska and the north central US to have injured turf when snow cover is not maintained throughout the winter. Over the long term, windbreaks can help to slow the wind across an area and encourage longer snow cover. In the short-term, a wide variety of turf covers, from fabrics to snow fences to late-season topdressing can help prevent desiccation. When feasible, winter irrigation can help maintain plant and soil moisture and also minimize damage from desiccation.
The recent winter winds have blown away just about everything that wasn’t nailed down. Double check to make sure your mulch around tender perennials hasn’t blown away. If it has, you may need to replace it. Reapply the mulch as needed, make sure to maintain a depth between 2-4 inches of material. The mulch acts as a buffer for the tender plants and keeps them from thinking it is spring prematurely.
When the winds happen to subside and the temperatures get warm again, it won’t hurt to drag out the hoses and water your landscape to save yourself from the damage later on in the year.
Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at elizabeth.killinger@unl.edu, her blog at https://huskerhort.com/, or HuskerHort on Facebook and Twitter.