Mulching
Mulch First, Then Compost
You may find it surprising that the first bit of advice is to avoid composting as much as possible by learning how to mulch various organic materials, especially grass clippings. Mulching is nature's recycling system. Nature spreads thin layers of organic materials evenly over the surface of the soil. Mulching simply refers to any technique where organic matter is spread in thin layers on the surface of the ground and left to decompose naturally so that soil organisms can convert it to humus. Decorative bark layered around shrubbery is a popular mulch. Wood chips are often spread around trees and landscaping to hold moisture. Grass clippings, leaves, and compost can be placed around garden vegetables, flowers, and in soil beds to keep down weeds.
Leaving blades of grass on the lawn is the most common mulching technique. All mulches help retain water in the soil. Mulch keeps the soil cool in the summer and warm in the winter. In fact, mulch is a form of drought insurance. Mulching is the easiest way to avoid generating organic waste in the first place. Leaving grass clippings on the lawn is the simplest type of mulching. But mulching is not practical for all residents and homes, and not all yard trimmings are easy to use as mulches. Brush must be chipped before it can be used as a mulch, and few residents own brush chippers. Many communities operate municipal wood trimmings collection and chipping programs with the wood mulch used in public areas such as parks and roadways. There are Christmas tree mulching programs in Ada and Elmore Counties.
How to Mulch Grass Clippings
The easiest way to start mulching is to take the grass catcher off the lawn mower. This tip is so important that it bears repeating. Take the catcher off your mower! Your mower service shop should be able to put a trap door over the discharge end if your mower does not already have one. For conventional side discharge mowers without a trap door, mulching may require a bit of raking following mowing to break up the little rows of clippings. To avoid raking the entire lawn, mow from the outer edge in ever-smaller circles toward the center, making sure that the side discharge mower is "walking" or blowing the grass clippings ever closer to the central point. In this manner, clippings are chopped several times and most fall between the blades as mulch. The few that are left near the center can easily be raked and placed into the compost bin or spread in the garden.
Consider a Mulching Mower
Mulching mowers have become quite popular in recent years and dealers proudly display their new features. Advertising campaigns are helping convert homeowners to these new "zero discharge" mowers. Mulching mowers are designed differently from conventional mowers with closed trap doors. The first difference is, of course, the lack of a discharge point and a catcher. The second is the horsepower rating, since mulching mowers require more horsepower to cut and re-cut the grass. The special blade not only cuts, it also acts as a vacuum and fan that circulates the clippings back to the blade for additional pulverizing. The air pressure then forces the chopped clippings downward into the lawn. Even replacing your regular cutting blade with a mulching blade can turn a regular mower into a better mulching mower.
Mulching mowers require a lawn that is not overly wet and has not been left too long between cuttings. The height of the grass should be somewhat higher than typical settings for bagging mowers and the lawn is best cut when the grass is one third higher than the height of the blade. For the average lawn, if the grass is left at two inches following mowing, the grass would be cut when it reaches three inches. While the new system takes some getting used to, user satisfaction is running near 100% for those who have made the switch. The lawn must be mowed more often than with conventional mowers, but the time actually spent in the yard is less because there is no need to continually stop and empty the catcher. Mulching mowers should be used every five to six days instead of every week.
Cutting grass higher with only one third the blade height is easier and faster than cutting overgrown grass. Fertilizing can be decreased since grass clippings contain 4% nitrogen and act like a time release fertilizer when they are returned regularly to the soil. Grass clippings return to the soil to form organic humus that helps hold water while keeping the soil loose and aerated.
The Economics of Mulching
Mulching can be viewed as an economic issue. Leaving yard trimmings at home is a means whereby the homeowner can stop paying for the plastic bags, the trash hauler, and the waste disposal operation. Mulching means lower taxes. With mulching and composting, householders can manufacture their own topsoil and soil amendments. At three dollars per cubic foot bag at the garden center, one cubic yard of mulched yard trimmings represents a saving of over $80. If one cubic yard of compost can be blended to make ten cubic yards of topsoil, then a yard of compost can equal one truckload of black dirt worth at least $100. In addition to the cost benefits, you also reduce your dependence on landfills while experiencing first-hand the satisfaction of conserving natural resources. Like those who enjoy feeding wild birds, mulching is a means of feeding the soil ecosystem and the associated plants, trees, and landscape that give us pleasure while beautifying our homes.
Leaves
Leaves can also be mulched. Leaves left on the ground over the winter will not harm the grass, which goes dormant in most climates. In the North, winter puts leaves through a "freeze thaw" cycle that helps soften them for decomposition. Winter snow and Spring rains provide needed moisture for the subsequent breakdown.
Leaves can be gathered and placed into wooded areas for mulching. They should be spread evenly, never more than six or eight inches deep. Random and unattended piles several feet in height are neither a mulch nor a compost. Take the time to spread your leaves evenly so that they can decompose properly. If you have no natural undergrowth areas on your property, be sure to ask permission of any adjacent landowners to spread leaves in their woodlands before using it as your disposal site. At no time should you use vacant lots, public parks, ditches, rural areas or piles over the fence as dump sites. Many communities have a program whereby local farmers allow householders to bring their leaves out to the farm for spreading in the fields. Mulching is the beneficial use of organic matter that also happens to solve a disposal problem. Dumping leaves is a public nuisance and is often punishable by fines.
Chopping, shredding, or mowing the leaves before using them as mulch can assist leaf mulching. Care must be exercised when handling dangerous chopping equipment. Make sure that your machine or mower is rated to handle leaves and that all necessary safety precautions are used. Safety glasses, gloves, and heavy clothing are wise items to wear during all pulverizing operations. Leaves that are placed in large piles in the fall tend to insulate themselves and shed water, delaying decomposition. The following Spring the leaves look much like they did months before. If leaves are gathered in the Fall, they should be moistened several times, layer by layer, to aid decomposition. Soil wetting agents sold at garden centers or through organic detergent retailers assist in the process of getting dry leaves to take on moisture. If possible, spread leaves over the garden, in flowerbeds or wherever there is open soil. The three keys to getting leaves to decompose are watering, moisturizing, and wetting. And then they should be watered again.
Earthworms: The Mulching Assistant
Earthworms are the ultimate mulch specialists. The common night crawler, lumbricus terrestris, is a seasoned mulch hunter. Following every rain, or in the cool, moist mornings, hundreds of earthworms come to the surface to feed. These "mulch munchers" grab leaves, blades of grass, and other bits of organic matter and "tow" them back to their burrows. Deep under the soil, these worms store organic matter, excrete digestive juices to help them decompose the matter, and feast upon the resultant compost at a later date. The worm devours the decomposed mulch and deposits the humus both in the burrow and on the surface as earthworm castings. Since the worms continually excavate and turn the soil, the humus layer remains near the root zone while the surface is continually cleared of debris. Earthworms will maintain a population level equal to the available feed or mulch. They keep the soil loose, aerated, and well drained. Working in harmony with other organisms, earthworms turn under the seasonal mulch layers, "vermicompost" it, and convert it to available plant nutrients.
Many gardeners have had success introducing red worms such as eisenia fetida (the common red or "brandling" worm) or lumbricus rubellus (the red wriggler or so-called "hybrid" red worm) to their lawns and gardens. Red worms devour the humus layer of the soil voraciously, quickly turning mulch into castings. Native to temperate river deltas, red worms require a moist, well drained, rich topsoil with plenty of mulch and organic matter. They will not burrow to escape the frost and drought, however, as do their night crawler cousins. They will only live for a few months in the lawn or garden in most climates. Red worms may have to be replenished annually in the humus-enriched or mulched garden and lawn. Always remember that red worms cannot make a poor soil good, only a good soil better. The aeration and mulching benefits provided by red worms is hundreds of times that of the less active night crawler. A few dozen red worms purchased at the bait store or a few thousand ordered through the mail from garden catalogs are often sufficient to get started. They breed like crazy and will quickly increase their population to handle any volume of household organics.
Many people add red worms to their compost pile and let them quickly eat the table scraps and other organics stirred into the top layer. Red worms will enable the pile to decompose much more quickly than letting it sit passively. The best thing about earthworms is that they do the mixing and aerating all by themselves, living on the decomposing compost and the regular addition of discarded fruits and vegetables. You don't have to turn the pile to get it to cure when you let red worms do the work for you. But red worms should not be used if you are making active batches of compost. The heat will cook them or drive them to the edge of the pile, often to their death. If using active composting techniques, wait until the pile has cooled before adding red worms.
Many people use red worms year-round right inside the house to take care of their table scraps and a limited amount of shredded paper products. In the basement or under the sink, they keep them in plastic bins that are less than one cubic foot in size. As long as they are kept warm, moist and protected from light, one small worm bin per person will consume the daily production of vegetable and fruit discards along with the coffee grounds, filter and all, on a year-round basis.
Worm farmers need to periodically remove the rich earthworm digested compost, called "worm castings," as worms do not like living in their own manure for more than a few months. Worm castings, however, are worth the effort of indoor worm ranching. This "super compost" is the best ingredient in potting soils and is valued above all other compost products. Experienced gardeners will point to the soil worms in the garden and the red worms in the worm bins as the secret to their exceptional yields.
