In the natural world, the endless cycle of birth, growth, decay, death and rebirth flows throughout the seasons. Plants die, leaves fall and new growth springs up in its place. Nothing is wasted: the fallen leaves and dead plants decay into the soil, enriching it for the next generation of growth. The accumulation of these dying materials is known as mulch and it is a vital aspect to replenishing the nutrients of the soil for sustaining plant life.
Mulch makes ugly drip systems disappear. Mulch miraculously turns bad soil into good soil. Mulch can help transform a small one gallon plant into a full grown shrub or help turn a sapling into a tree. Mulch can disguise damp newly irrigated soil so that it looks dry on the surface. For these reasons and many more, mulch is magical.
All too often, we rake up the leaves and clear the space around our plants which deprives the soil of this much needed regeneration. Mulch (partially decomposed organic material) can be applied to the open spaces of any garden to remedy this situation. It is visually attractive and not only replenishes the nutrients in the soil but has the added benefit of insulating any water applied to the garden from sunlight that evaporate irrigation water. Mulch can be any material that can be placed on the surface of the soil to conserve moisture and prevent weeds from growing.
On Bare-Soil Pathways and Unplanted
It is helpful to apply four to six inches of mulch on bare-soil pathways and unplanted areas to prevent compaction and erosion. Mulch will also regenerate or enrich heavy clay soils.
To prevent grass and weed growth around the base of young trees, apply two to four inches
of partially decomposed organic matter (mulch) at least two feet out from the trunk. Leaving an open space near the trunk will prevent damage from weed-whackers and lawn mowers.
Around Woody Perennials and Shrubs
Apply two to four inches of mulch to help maintain soil moisture. Adding more - four to six inches deep - will also help prevent weed growth.
Around Vegetables and in Flower Beds
Apply one to two inches of straw or composted manure; this is best for annual plants because it breaks down quickly.
Recycle Green Waste as Mulch
Allow falling leaves to remain on the soil as mulch. Leaves can be shredded with a lawn mower and collected in a mower bag to be spread under shrubs. This will keep them in place in mulched areas and speed up their decomposition.
Eventually, mulch will decompose and break down. Weed seeds will blow in and grow without the insulation of mulch. Reapplying a one to two inch layer of mulch every six to twelve months (in fall before the rainy season, and in spring) is the key to preventing weeds from becoming established. A fresh layer of mulch will keep your garden looking clean and weed free.