Benefits of Mulching Your Garden
Mulch is an excellent way to control weeds and protect garden soil. It also helps with temperature regulation and retains water to hydrate plant roots.
Choose organic mulches like compost, grass clippings, shredded leaves or well-rotted animal manure (ensure it has been allowed to rot for at least two years, or it will scorch the plants). Biodegradable mulches break down over time, enriching the soil with nutrients.
Reduces Soil Erosion
Mulch helps prevent soil erosion by smothering the weeds that usually grow in exposed soil and holding water and nutrients. It also reduces the force of rain and wind on the garden and prevents evaporation from the soil surface. This is especially important for hilly and sloped garden areas.
Organic mulch materials like grass clippings, leaves and compost decompose over time to nourish the soil below. A 2-inch layer of mulch can cut summer evaporation from the soil by up to 20% and insulates roots against temperature extremes. It also helps protect trees and shrubs from frost-heaving and winter damage. And it adds organic matter to the soil that earthworms and other beneficial organisms can digest.
Prevents Weed Growth
Mulching helps suppress weed growth by blocking the sunlight needed to grow weed seeds. This helps reduce weeds and the use of chemical herbicides.
A thick layer of mulch will also help conserve soil moisture by reducing water loss from the soil’s surface. This is particularly beneficial during hot summers.
Organic mulches, like compost, grass clippings and shredded leaves, will improve the nutrient content of the soil as they break down. They also benefit the structure of the soil by improving aeration.
Other types of organic mulches include garden compost, wood chips, well-rotted manure, leaf mold, sawdust, peat moss and cocoa shells (though it is best to choose a mulch that has been treated so it doesn’t contain theobromine if you have pets). Hay, however, should be avoided as it often contains weed seeds.
Increases Soil Fertilization
A layer of mulch adds organic matter to the soil. As it breaks down, it helps improve the structure of clay soils and increases the moisture-holding capacity of sandy soils. It also slows the loss of nutrients from the soil and makes micronutrients already in the ground more available to plants.
It keeps weeds from growing and reduces competition for water and nutrients by locking in the soil’s moisture. It also moderates soil temperatures, keeping it cooler in summer and warmer in winter, which can prevent root damage during frost-heaving.
Mulch should be applied in the spring before any direct-sown seeds sprout. Using a light layer of compost or well-rotted animal manure is best for vegetable gardens, as it will help the soil become richer.
Deters Pests
A layer of mulch suppresses weed growth, holds in moisture, prevents soil-borne fungi from splashing on leaves during rain or watering and moderates temperature extremes. It also protects trees from early frosts in the fall.
Depending on the type of mulch, it can also deter pests. For example, wood chip mulches containing aromatic oils repel insect pests.
Organic mulches can be made from garden compost, wood chips, ground-up hay, leaf mold, well-rotted animal manure and straw (for strawberries). These slowly break down to improve the soil’s structure and add nutrients. They are a good choice near fruit bushes and trees because they help retain soil moisture, which can prevent problems like blossom-end rot on tomatoes and frost damage in the winter. This allows you to reduce the frequency and amount of watering.
Keeps the Soil Moisturized
Mulch moderates soil temperature fluctuations, keeping it warmer on frosty nights and cooler on hot days. It also helps to prevent the cycle of freezing and thawing that can push plant roots out of the ground in cold climates.
Organic mulches like hay, straw and composted leaves add valuable nutrients as they break down. They also build optimal soil structure, creating a spongy texture favored by vegetables.
Newspaper is a cheap, biodegradable option that offers weed suppression, soil moisture retention and improved soil composition as it decomposes. However, it may rob the soil surface of nitrogen, so apply some extra nitrogen fertilizer before spreading it. Cocoa bean hulls are another affordable and attractive option. They provide good insulation and weed control, resist compaction and add a pleasant chocolate scent to the garden.