According to Environment Canada's ubiquitous chief climatologist, David Phillips, this winter looks like being drier and warmer than normal. While greeted with glee in some quarters, it is definitely bad news for gardeners seek to overwinter their precious perennials. Snow is what they want. But snow is not what they are likely to get, not if Mr. Phillips is right.
Snow is an excellent insulator, nearly as good as a down quilt, wrote Matthew Sturm in last May's
Scientific American. This, he explains, is because the snow pack may be as much as 75 per cent air. In those parts of the Arctic where the deeper snow insulates the ground better, soil temperatures are higher than they would otherwise be, Sturm notes.
Also in the Arctic, the taller shrubs are more efficient at trapping snow, helping them flourish. The advice rendered with regard to ornamental grasses is to leave them standing overwinter for the same reason. They also add winter interest to the garden, both to look at and listen to the rustling of their leaves . . .
Snow is in fact superior mulch. Gardeners in Toronto may find it a challenge to overwinter perennials, where as the same plants 50 or more kilometres north in the snow belt survive with ease.
This is snow that accumulates naturally, not that resulting from shovelling, snow blowing or ploughing. These latter pack down into a solid, air-excluding mass, threatening to choke the life of anything unfortunate to be buried beneath.
In larger, more open urban gardens as in rural areas, snow fencing might be erected to slow the force of the wind. This will result in a load of snow being deposited as the wind loses its snow-carrying energy. The catch here is that such fencing must be erected several yards away from the area it is desired to keep clear.
For a final note of warning we must return to David Phillips. Don't stick out your tongue to catch the flakes: "There is no such thing as pure driven snow," he warns. Snow begins with a nucleus, which can be a speck of dust, or salt, or spore, or bit of pollen, he told the
Toronto Star. Or the result of particles from a smokestack. Burp. Pardon.
