From South Carolina to New York and points further North, this weekend was full of winter precipitation. Rain, snow, sleet and … well, you know the saying. Monday morning, the questions came rolling in from concerned gardeners – will the snow and ice hurt my garden? my lawn? what should I do? The simple answer is “relax”, and I’ll tell you why.
Nitrogen: There are two old sayings worth mentioning here, the first being, “Year of Snow, Crops Will Grow.” The second calls snow “Poor man’s Fertilizer.” Precipitation captures atmospheric Nitrogen molecules, and studies show that snow does a better job of this than rain. The Nitrogen comes from many sources, but the most prevalent is industrial output. This map shows the concentration of atmospheric Nitrogen and its concentration in industrial areas of the United States. http://nadp.isws.illinois.edu/lib/brochures/nitrogen.pdf
Another major source of atmospheric Nitrogen is lightning activity. The Nitrogen added to the soil by precipitation is not as concentrated as one would find in a chemical fertilizer, but it helps. Now I am not an advocate of pollution, but precipitation does, in fact, clean the air, and contributes Nitrogen, Carbon and trace minerals to our soil.
Insulation: A layer of snow protects the plants in much the same way as a layer of mulch. The soil temperature is stabilized, protecting tender roots from radical temperature changes like deep freezing or abrupt thawing. Deep freezing can inhibit the activities of earthworms and beneficial micro-organisms that are still active in the Winter, breaking leaf litter down into compost. Quick thawing can heave the soil, damaging roots. Plants covered by snow are protected from the drying winds of Winter. But here’s one of the aforementioned caveats – heavy accumulations of snow and ice can damage shrubs and tree branches, so, if possible, gently remove heavy snow to avoid splitting and breaking. Snow covered ground can also act as an insulation system for irrigation pipes, protecting them from cracking and bursting.
Nature’s Drip Irrigation: Rain soaks into the ground to the point of saturation and then runs off. Snow melts slowly, allowing the moisture to be absorbed more deeply into the soil before it starts to run off. The actual depth of moisture penetration is dependent upon the depth of the snow, the permeability of the soil, and the pace of the temperature change. Deeper moisture penetration means deeper penetration of the Nitrogen found in the precipitation as well. Caveat number two – snow treated with salt or chemical ice melt products can be harmful to gardens and lawns. Avoid piling treated snow on your landscape.
Snow as a Pesticide: Warm Winters mean buggy Summers. Snow, ice, and cold temperatures may kill off some of last year’s insects, leaving us to deal with newly hatched bugs, but not with as many over-wintering bugs – specifically Emerald Ash Borers and Japanese Beetles. Mosquitos, unfortunately, seem immune to cold Winters. This is an important part of the balance of Nature – organic pest management. Low Winter temperatures can kill off fungi and some bacterial diseases as well.
So rest assured that the recent precipitation is good for your Personal Eden! Now where did I put my seed catalogs?