Is it a good suggestion to spray my boxwoods and different evergreens with an antidesiccant this fall? I want to plant some extra boxwood this fall for the reason that climate is so good.
― Edward Cole, Willowbrook
Evergreens lose water by way of their leaves in a course of referred to as transpiration. Antidesiccant sprays are used to cut back this water loss throughout late fall and winter. The bottom across the root system can freeze strong throughout severely chilly climate and freeze deeper when there isn’t any snow cowl or mulch to assist insulate the soil. The frozen floor can lower or cease the uptake of water by the vegetation’ roots. If the climate turns heat and sunny whereas the bottom continues to be frozen, evaporation will increase and discolored or “burned” foliage could begin to seem.
Winter burn could be extra prevalent in years during which the bottom freezes early earlier than vegetation are acclimated to chilly climate and when there’s a lack of snow cowl. The brown or yellowed foliage is usually discovered on the facet of the plant going through the solar and/or wind, the place evaporation is biggest. Winter burn signs sometimes develop when temperatures heat up in late winter and early spring. Such a winter injury could be misdiagnosed as a illness or injury from excessively chilly temperatures.
The boxwoods and different evergreens which have been rising in your backyard for greater than three years and are nicely established shouldn’t should be sprayed with an antidesiccant. It is very important water evergreens planted during the last two to a few years if the climate is dry and heat this fall in order that they don’t go into winter underneath drought stress. November is beginning out comparatively heat, so some supplemental watering could also be warranted. It’s a good suggestion to offer supplemental water to new vegetation in November to cut back the possibility of winter burn. Newly planted evergreens are inclined to shed rain away from their root balls (the place most roots are situated) till they set up roots out into the backyard mattress, so water on the base of those newly put in vegetation.
Putting in evergreen bushes and shrubs in late October and past does improve the probabilities for winter burn because the vegetation have little time to ascertain roots earlier than winter units in. Making use of an antidesiccant spray to those vegetation could also be useful in getting them established. I planted a number of 6-foot-tall upright yews in the course of November one yr throughout a chilly spell that had frozen the basis balls earlier than planting. These vegetation had a superb quantity of winter burn the subsequent spring however did recuperate. The vegetation had been skinny the primary summer time as all of the winter-burned leaves fell off.
Totally different gardeners present completely different recommendation on how late to plant evergreens. The sort and measurement of the evergreen you might be planting and the place within the backyard it’s sited will have an effect on its probabilities of winter burn. I feel it’s OK to plant extra boxwood in your backyard this fall. You may cut back the possibility of winter burn by selecting the best plant to your backyard’s rising circumstances and siting it correctly. Correct planting, together with mulching and watering this fall, will assist.
Salt spray from site visitors can injury evergreens in addition to deciduous bushes and shrubs. The salt attracts water out of the plant tissue and dries it out, inflicting one other sort of winter burn. Vegetation situated close to dryer vents or furnace vents will also be broken in winter by the new air.
For extra plant recommendation, contact the Plant Info Service on the Chicago Botanic Backyard at [email protected]. Tim Johnson is senior director of horticulture on the Chicago Botanic Backyard.