Possibly derived from the Old English word mylsc, meaning mellow, or from the Middle English word molsh, meaning soft or moist, mulch is a layer of protective material which covers the soil. Mulch helps the soil stay moist, regulates temperature, protects soil from solar UV rays which has a sterilizing effect, reduces weed growth and slowly improves soil fertility as matter breaks down.
Mulching, as a practice is millennia old. Some of the earliest references to mulch (green manures) are recorded in Chinese writings from ca. 500 B.C. (Paine, Laura K. and Harrison, Helen, June 1993. The Historical Roots of Living Mulch and Related Practices, Sustainable Horticulture, Department of Horticulture, University of Wiscosin). Lithic mulching has been documented as early as 200 B.C. in the Negev desert (Kedar, Y. 1957. Ancient agriculture at Shivtah in the Negev. Israel Exploration Journal. 7:178-189).
How to Mulch (find it on Amazon US, UK, IN) by Stu Campbell and Jennifer Kujawski describes how to use mulching to save water, suppress weeds and trickle feed the soil with nutrients. The book takes a look at sheet mulching, feed mulching and the use of living mulches as methods to protect young plants and to boost garden and farm productivity.
Mulch provides your soil with a steady and slow release of nutrients while helping retain moisture and absorb precipitation. This means a reduced dependence on watering or irrigating plants, allowing for your time and energy to be spent on lower priority farming or gardening activities. Mulching prevents weeds from overtaking the growing bed and it regulates soil temperature. Most importantly, mulch helps promote biological activity and proliferation of beneficial organisms. Check out Anna Hess’ The Ultimate Guide to Soil (find it on Amazon US, UK, IN) to get an encyclopedic overview about managing soil and in-depth information on mulches, manures and composts.
Types of Mulch
While many commercial farms tend to use inorganic ground cover like such as stone chips, UV protected plastic sheets or fabrics, most organic and permaculture farms, homesteads and gardens prefer organic mulching which adds back to soil health. Many operations also prefer using living mulch or groundcover which can also provide an additional crop. Most organic mulches require care and replenishing.
- Leaves, which fall or are trimmed, are a popular form of mulch because they are generally available right on one’s property or easily available. A mix of leaves from a variety of plants will usually provide ample ground-cover and they will decay into nutritious food for soil organisms. Avoid leaves from poisonous plants or those which are extremely pungent since these can be toxic to the immediate soil environment. Most leaves however will dry and decay, adding to the soil’s wealth. Don’t forget to get yourself a leaf blower (find one on Amazon US, IN) and a dependable rake.
- Wood and bark chips are also popular, especially in areas where the local municipal undertakes continuous aggressive pruning along roads, highways, railways, public property and near power lines. If you cannot access wood and bark chips you might be able to produce your own if you have trees and bushes which require pruning. Wood chippers are available in a variety of sizes ranging from small ones (find it on Amazon US, IN) suitable for home gardens, medium sized chippers suitable for homesteads and small farms, to industrial chippers which are ideal for large properties or commercial farms. Wood chips break down slowly and are suitable for wide open spaces which are not being cultivated.
- Grass, straw and hay is another popular mulch, usually used around planting beds and young plants. Easily mowed or procured from local farms, grass or straw deteriorates quickly unless heavily applied. Straw bales can even be found online and be used as a growing medium as described in Straw Bale Solutions (find it on Amazon US, UK, IN) penned by Joel Karsten.
- Peat moss and pine straw/needles are often used around acid loving plants and trees, as these lower the pH level of the topsoil. Peat moss is composed of plant material (usually from bogs and marshy areas) which has not fully decayed. Peat moss absorbs water and is a useful mulch in any farm or garden’s water conservation efforts. Pine straw mulch makes for an attractive ground-cover.
- Newspaper and cardboard make for good mulch material. Most printers have moved to eco-friendly inks which degrade naturally along with the paper. Paper and cardboard blocks light out to keep weeds away while holding moisture in, making it a good short-term mulch material that’s useful around young plants and saplings.
Also known as ground-cover, living mulch comprises fast growing plants which proliferate close to the soil. Many agriculturists prefer to use multiple varieties of living mulch, including nitrogen fixers like clovers and crop plants like field peas, cow-peas and velvet beans.
Open spaces provide an opportunity for productive grasses like rye-grass, annual rye-grass, pearl millet, barley and oats, and legumes like alfalfa, red and sweet clover. Peanut and pea ground cover crops also provide a cash revenue opportunity. Have a look at Managing Cover Crops Profitably (find it on Amazon US, UK, IN) by SARE Outreach, to learn how to build cover crops into a farming operation.
Compost too is a preferred mulching technique, although many farmers and gardeners apply an additional organic mulch layer over this. There’s a scalable plant super-food compost recipe that’s available on HappyDIYhome. It’s a fantastic go-to on various kinds of mulches, gathering mulch material and making your own compost affordably.