Dear Plant Ladies
Riverwoods Plant Ladies, Margie Kaul and Shiela Hollander answer your plant questions.
The snow is so deep that my plants are buried. Is this a good thing or a bad thing? – The phrase “blanket of snow” is more than a visual description – it’s accurate in terms of warmth. Snow is an excellent insulator for gardens, landscapes and hibernating animals by protecting against low temperatures, damaging winds and temperature fluc-tuations. Snow cover protects buds, foliage branches, stems and roots. Generally, temperatures beneath a layer of snow increase about 2 degrees for each inch of accumulation.
Okay, so snow is a good thing. How exactly do the plants benefit? – Needle evergreens such as Yews and Rho-dodendrons and Boxwoods are susceptible to winter burn. They lose water in cold weather through their leaves. The snow cover provides insulation and moisture retention. In the spring, flowering shrubs will bloom more heavily if they spend the winter below the snow line. Also plants with shal-low root systems, like perennials, ground covers and bulbs, can be pushed up out of the soil by temperature fluctuation. The snow protects them from drying out due to the cold and wind.
Okay, I’m freezing but I’m becoming a believer. Any other benefits? – Snow enriches the soil with nutritious ele-ments, so you may not realize it, but you’re fertilizing just as the snow melts and is being absorbed.
What about my shrubs buried and covered with ice? – I know the tendency to knock the snow off is strong, and if there is a day above freezing you can GENTLY brush off the snow to free the buried branches. However, they will be very brittle and will break easily. It’s probably best to just leave the plants alone and let nature’s melting take its course.
Okay. That’s news about snow. What about the ice on my driveway? If I protect myself from a fall, am I also killing my plants? – Most deicing salts use chloride and sodium, both of which can damage plants. Plants can absorb the chloride in the salt, which can lead to dieback. Sodium in the salt may destroy soil structure, which leads to poor drainage and root growth. The preferable type of salt is mag-nesium chloride. It will melt the ice until the temperature reaches -13 F. It releases about 40% less chloride than either of the other two types of deicing salt, which are sodium chlo-ride or calcium chloride. It is also much less toxic to plants and animals.