Nature’s Garden
What a weird winter. Instead of enjoying infrequent, yet tempting, tastes of spring, it seems more like spring with occasional bouts of snow and cold.
During the first week of January in my garden I saw the perky, yellow faces of primroses, dozens of pale, pink flowers on my creeping phlox, and dandelions blooming in the lawn. Buds on my shrubs are plumping. I see new leaves beginning to push up from the base of herbaceous perennials. And the garlic bulbs I planted in fall have sent green shoots up, 4 to 5 inches tall.
In Pittsburgh this past weekend, I noticed the pussy willow bush of a friend has begun producing silvery catkins. In Washington, D.C., the cherry blossoms are opening early. And fruit farmers across Pennsylvania are concerned about this year’s crops.
Winter is supposed to be a time of rest for these plants; a time of dormancy. For many species there is a certain quota of chill time needed. Somehow, plants are able to calculate or keep track of the length of time spent near freezing. Only after they meet their requirement can they bloom.
Typically, the further north you go, and the higher in elevation, the greater the chilling requirement. This is one of nature’s methods to help ensure that plants don’t bloom too early in spring. The purpose of flowering, of course, is reproduction. If flowers are damaged by cold, reproduction doesn’t occur. You get the picture.
Species that have shorter chill requirements-for example, plants that are marginally hardy in our climate-can be prompted to break dormancy earlier with warm days. Flowers such as snowdrops, witchhazel and others can take cold weather just fine. Other plants can’t.
The absence of snow cover also is a bit of a problem, I think. Snow is an excellent insulator and I rely on it to protect plants in my garden. Under a nice blanket of snow, root growth continues underground while the rest of the plant rests. Without this blanket, when it does get cold, the ground freezes much more deeply, which also can be a problem for earthworms and hibernating chipmunks and toads.
Snow also helps retain moisture in the soil through winter. Even though plants don’t absorb water very quickly in winter, they still need it.
And, another thing: When temperatures are warmer there may be too much activity of plant pests when plants aren’t active enough to defend themselves. Snow can provide some protection from pests, too.
Sometimes I think trees and shrubs are the plants that take a greater hit when it is too warm in winter and then the temperature plummets. All through the fall, trees geared down for their winter dormancy. Tough sheathing over buds developed to protect next season’s foliage and flowers. If the tree or shrub accumulates enough chilling time and leaves and flowers begin to emerge, they are at the mercy of the fickle weather. Cold temperatures can kill young foliage and flowers as fast as you can say, “Jack Frost,” and there can be extensive twig dieback, too.
One of my trees, a catalpa, displays what appear to be several distinct frost cracks in the bark of its trunk from cold weather temperature fluctuations in years past.
Fortunately, trees, shrubs and other plants can usually survive the damage of a weird winter or two. Healthy trees and shrubs generally will releaf if the first flush of foliage is killed by cold.
But leaves are one thing, flowers are another. These unusual January flowers I’m seeing in my garden, I’m enjoying them now.
Most plants only set so many flower buds in the fall for the following growing season.
Any flower buds prompted to open early and killed by the cold between now and the true arrival of spring will only decrease the floral show we see later this year.
—
Susan Brimo-Cox gardens, observes nature and writes in Ohiopyle.
Readers can send questions or comments to her at naturesgarden@brimo-cox.com.