Self-Taught Gardener: Reliable ground cover
As my dog Fred and I traversed the byways of the Midwest, driving from Minnesota to Iowa to Chicago for the holidays, I had a lot of time to daydream. Time in the car is always contemplative for me, and the landscape always influences my thoughts. As we passed through the snow-covered fields and prairies of eastern Minnesota and across Wisconsin, I ruminated on the seasons and what they mean to us, as gardeners and stewards of the environment.
Except for some minor pruning, I am not in the garden much during the winter. This gives me the chance to step back and contemplate the garden from a distance. As I drove through Sun Prairie and Madison, with snow-covered fields to one side and a median filled with trees and wildflowers to the other, I thought about snow, fallen leaves, common evergreen ground covers like vinca and pachysandra and their role in protecting the soil in fields, woodlands and gardens from erosion by wind and rain.
Ground covers, snow, and decaying leaves protect the soil below by shielding it from wind and rain. Contrary to our President’s comments on the California woods needing to be cleaned (his view of what caused the fires that swept the West Coast), leaves and detritus serve a purpose even in the more temperate regions of the country. They add organic matter to the soil and they also serve as a protective cover from erosion due to heavy rains, which seem to fall in California and across the country with increasing regularity these days (almost in contrapunto to the wildfires in California.) Norwegians know this (despite the President’s claim that the Norwegians clean their woods to prevent fires, the Norwegians do not remove such things from their woods) and gardeners do, too. While leaves left on a lawn might cause dead spots in the grass, leaves in the garden protect the crowns of perennials and vernalizing bulbs of daffodils and tulips from frost/thaw cycles, or premature leafing out. While slowly decaying and adding organic matter to the soil, leaves also help retain moisture and keep the soil from blowing away.
As I passed field after field, and as the snow cover went from a foot thick to nonexistent, I realized that one important protector of our soil in Northern climates has been lost over the past few years — consistent snow cover. For most of my life, I remember snow covering garden beds and fields from December through spring. Now, in an age where the weather is more variable, we can no longer rely on this protection. Plants and soil are exposed to 50-degree temperatures one day and 10 degrees the next. If I am confused about what coat to wear as I head out the door to drive home for the holidays, imagine what happens to the poor plants and their systems for maintaining dormancy.
Chicago had quite a cold spell in October and November, with snow early in the season, but as I arrived for the holidays, temperatures were on the rise and the early snows were gone. As I arrived at my mother’s house, I leapt out of my car, jacketless, and walked to the back door, only to look down and see the gray-green foliage of daffodils beginning to poke through a patch of bare soil in the bed alongside her house. I wanted to lay my unused overcoat over the bed, or to cover it with snow to provide the bulbs with the protection they may need in the months to come, but realized the best thing that I could do was to head to my mother’s yard, gather some leaves from along the side of her garage and cover the bulbs, so that they would rest quietly until spring. While I prefer the idea of the beds being covered with snow that would slowly melt and nourish the bulbs when they leave dormancy in the spring, I realize that the only cover I have for them is what I have on hand. As I finish covering the bed with leaves, I bid adieu to the bulbs underneath until a more appropriate moment comes for me to welcome their emergence.