White Christmas? We can only hope. Not just because snow makes the holidays so much more picturesque, but because it does wonders for a garden.
Last year we had snow cover almost all winter — common up north, but unusual in more southerly parts of the Midwest. Then we had the most spectacular spring. Bulbs flowered like crazy; trees flowered grandly; grass was lush and green; shrubs put on new growth faster than I’d ever seen them. Why?
The snow — which after all is mostly air — acted as insulation. It kept bulbs and root systems safely dormant, so they didn’t spend any effort responding to winter warm spells by trying to sprout or open their buds. Digging down in January, I found my soil solidly and safely frozen.
When the snow finally melted, it bathed awakening bulbs and roots and sprouting seeds. Snow is only about 10 percent water, but still, 15 inches of snow will melts to provide the equivalent of an inch and a half of rainfall. That’s a good start.
Sprouting when it was truly time, the plants had plenty of water, sunlight, nutrients and energy to grow and flower and put on a big show.
Places up north, such as Minnesota and southern Canada, reap some other benefits from being able to rely on a blanket of snow. For example, recently released varieties of Hydrangea macrophylla that are claimed to be hardy in Zone 4 actually tend to make it through the winter better up there than here in Zone 5 Chicago. Why? Minnesota is more likely to have that thick blanket of insulating snow. Some years, we get very little. That’s one reason I am compulsive about mulch.
It’s lovely to stand in a conservatory or greenhouse and watch snowflakes fall overhead. But in colder climates, snow that piles up also can buffer a greenhouse from the prevailing wind, reducing heating costs.
Of course if snow comes too early, you may not be ready for it. One year when I procrastinated about planting bulbs, a big early December snowfall made it a miserable chore. The ground was not yet frozen under the snow, but it’s not easy to dig through 8 inches of snow and then 6 inches of soil, and you can’t really tell if you are digging up perennials. This year I made a point of planting bulbs on time, in October and November. I’m eager for snow.