December 30, 2010 at 8:41 a.m.
Most of us in this garden game know that mulch is a very good thing. During the growing season, it helps retain moisture, maintains even soil temperatures, and helps keep the weeds down. In late fall after the ground freezes, a heavy layer of marsh straw, shredded leaves, pine needles, hay or snow, will keep the frozen ground frozen, protecting our perennials against soil heaving. The "freezing and thawing" cycles that occur during winter thaw periods can cause the ground to heave, exposing the plant crowns to wind and cold damage. Heaving can also break and tear the roots of trees and shrubs. This heaving process is the cause of much plant death when it occurs over just a couple of winters.
Snow cover is also called the Subnivean. The Subnivean denotes the area between the soil line and the insulative snow (niveus) layer. So it's a fancy word meaning "beneath the snow". Snow can be 99 percent air and this trapped air serves as nature's insulating blanket acting much like down. In addition, when the moisture from the snow soaks into the ground, the moist soil holds heat more efficiently than dry soil and retards frost penetration, thus protecting the vulnerable roots. In the case of evergreens, in particular, a good snow cover is the most valuable winter protection the trees can have.
Ever hear of "Snow Harvesting"? Just ask Master Gardener Jerry Vitalis and he'll tell you how he does some of this every winter on this blueberries. Snow cover is essential for blueberry survival so heaping on more of the white stuff will help ensure a healthy crop, even when temperatures drop to -30 degrees and lower. Think of it as a gardening chore, only this one is done in the winter.
So, to our great advantage, the snow came early this year. Had these amounts come later, say in late February or March after months of very little snow, they would not have provided the needed protection that a nice heavy early snowfall that sticks around does. For gardeners, and those that reap the benefits of gardening, the snow is going to be around for quite a while, and that's a good thing.