Fall Mulching - part of Mother Nature's master plan.
When the leaves have fallen and frosty nights cool the soil, it’s time to put your plants to bed with a new top-dressing of mulch. Applied this time of year, the benefits go far beyond the clean, neat appearance of freshly mulched landscape and garden beds.
Mulch has an insulating effect through the winter months. Cold air temperatures can affect plant parts above ground, but winter weather also does damage to plants if the soil and root system experiences extremely cold temperatures. Most people don’t realize root systems are less able to tolerate frigid temperatures than above ground plant parts, so mulch, whether nature’s plant debris or installed by man, serves to protect them through snaps of extreme cold.
Everyone knows that mulch saves water by preventing evaporation during the growing season, but few consider that the same benefit applies in winter! Plants transpire and lose moisture from bare stems during the cold dormant season. This becomes more important with evergreens (plants that hold foliage year-round) since the leaf surface adds to the moisture draw. (ex. Viburnum - Boxwood - Euonymus - Spruce - Arborvitae - Cedar - Holly)
Mother Nature shakes her head in disappointment-
After frost has taken its toll on our perennial plants, we tend to remove their wilted and dead foliage as a final fall gesture to gussy up everything for the long winter rest. Fall clean-up is a human instinct, but Mother Nature has her reasons for covering bare soil and making the autumn winds pile leaves up around plantings. Both the leaves and the old wilted foliage provide the services mentioned above – insulate the soil from temperature extremes and hold moisture. So, if we decide to do a season-ending leaf cleanup, we should always replace the debris with mulch to offer the same protection.
Bare soil is a BIG no no!
Bare, exposed soil is not a part of Mother Nature’s master plan. Soil is the foundation for ecosystem services and anytime it is exposed, nature makes moves to protect it. If there is not an adequate layer of mulch present, weeds emerge as a living, protective ground cover. Think about it; in fields, forests, lawns and gardens, nature doesn’t allow soil to remain bare for long. When soil is exposed to the elements, the millions of organisms we depend on for health are also exposed to same risks of temperature extremes, moisture loss and erosion. In just one teaspoon of productive soil, there are between 100 million and 1 billion soil organisms that we depend on for life. Furthermore, it takes between 100 and 500 years to build just one inch of life sustaining topsoil. Once we appreciate the natural reaction by nature to either cover bare soil with weeds, or with plant debris as mulch, we begin to understand that neither are there to oppose our gardening efforts; they’re simply providing the necessary service of soil protection.
And lastly, there are those times when a false spring comes early, warming up unseasonably in January or February often just long enough to entice plants to start growth before the freezer door opens again. Many plants begin spring growth based on soil temperature, not air temperature. Once again, mulched and therefore insulated soil warms more slowly, lessening the chance for damage from late frosts. So mulch your plants each fall and both they and Mother Nature will thank you.