Fall has come upon us. The weather was stormy and wet for a month, and now a "Polar Vertex" has appeared, bringing forth un-seasonably fridgid temperatures to begin November. With such a mild first half of autumn, the trees were holding tightly to their leaves, gathering the last precious bits of photosynthesis. Once the weather turns colder, and days shorter, the trees give up the fight. They pull the starches created in their leaves via photosynthesis to the root system. Over winter is when the tree concentrates it's energies to seek out underground niches to grow its root mass. With leaves gone, the tree has to expend less energy to fight the forces of nature upon the foliage. Wind exerts a great amount of stress on all trees, the deciduos species have an easier time of it during the dormant seasons.
Now nature teaches us a valuable lesson during the fall season. Leaves from trees falling to the soil are mulch. They create a layer of carbon that is full of nutrient for the microbes in the soil. A layer that holds moisture and covers any bare earth. Bare soil is bad news. Un-covered soil will quickly dry out, be succeptable to erosion and wind drift. Mother Nature always wants the soil to be covered in some medium, either a live or dead one. Permaculture teaches mimicry of Mother Nature and indiginous peoples methods of living with nature, not perpetually battling the systems presented to us. Observing a forest, we see bio-mass accumulation over decades. Natural succession, leaf and fruit drop, wind or fire disturbances, and animal interactions all aid in soil building. Humus is the stuff of life, holding moisture and the microbes for healthy soil.
Mulch can be applied anytime of the year, not just in the fall. I prefer to cover the beds in the fall, as winter will help to decompose the material. The mulch will also stop erosion during winter rains, and snow melt. Water will percolate into the beds under the mulch, and the mulch will help it from evaporating when the sun returns. If you mow a lawn, the grass clippings in the spring work wonders as mulch. Worms love to live in the wet, decomposing, nitrogen rich mass. Wood chips from a tree service, sawdust from your own cord wood harvest, rocks, straw, seaweed, and shredded newspaper all make great non-living mulchs.
Mulch gives a place for seeds to germinate, similar to a reproduction in nature, sprouting in the mulch of the deceased mother plant. Mulch helps the soil warm quicker in the spring and delay hard freeze late in the fall. We love mulch because it can keep pioneer weeds from wanting to colonize bare soil, and smothers grasses and other un-wanted species. Covered soils are more inviting to earthworms too! Underground tillers de-compacting soil, no back breaking labour for us, and they leave valuable castings to feed our plants.
Living mulches are another option for gardeners and farmers alike. Cover crops like white clover, alfalfa, field peas and vetch are wonderful as biomass accumulators and they also fix nitrogen. Seeds of these plants can be broadcast over a bed at various times of the year. Once they established you can remove patches of it and plant starts into it, leaving most of the mass intact. I love buckwheat for a mulch. Buckwheat grows quickly, self-seeds, and is frost killed. The flowers are a favorite forage for bees and other insects. It's leaves are edible, and the foliage makes a great mulch once "chopped and dropped". I also have a high regard for comfrey for a mulch. It is a bio-accumulator, with it's huge tap root that will bring nutrient and minerals up from the sub-soil, accumulating in the leaves. I can then chop those leave several times a season, without harming the plant. Comfrey also has great flowers for bees, and most varieties only spread from root cuttings, not seed. On small sliver of root with grow back as a full plant within a few months during growing season. Chickens love to eat it too. Comfrey is a magic plant!
If you are tired of weeding and watering constantly, look into mulch. People ask me what my number one suggestion is for implementing Permaculture in to their systems, and I always tell them "mulch, mulch, mulch!".