Mulch is responsible for the maintenance and protection of topsoil, and this is vital in sustaining our ecosystems and life cycles. Mulch nourishes, structures, guards and upholds the integrity of topsoil. The organic components of mulch guarantee that it will decompose.
Organic mulch will decompose. All living matter is colonized with many microscopic bacteria and fungi. These consume and break down mulch and are responsible for the nutrients in the soil. The interaction between the communities of microbes is called decay. Decay and decomposition are inevitable.
Different types of mulch include woodchips and bark mulch, and these two are the most frequently used. Woodchips take a while to decompose, about four to seven years. Bark mulch is more durable and has a life duration of seven to ten years.
Does Mulch Decompose?
Organic mulch will, in due course, decompose. Whether it takes several months or years, mulch will eventually need replacing. As mulch deteriorates, it contributes significantly to the soil- by adding organic humus.
Woodchips need about six months before they can be considered effective in mulch. Aging is necessary as soil microbes consume the plant matter of the wood chips. Fungal components and microbial interactions have a symbiotic relationship. This relationship is known as decay and is crucial to the health of your soil.
Mulch provides nutrients to your soil; it retains water and ensures the integral structure of the earth. Mulch prevents a significant portion of moisture from evaporating from the ground. It is therefore vital to the maintenance of land during a drought.
Factors That Determine the Rate of Decomposition
The rate at which mulch decomposes depends on the nitrogen level in the soil. Nitrogen is critical to plant life as it comprises the molecules in chlorophyll and generally in amino acids, which are proteins on which life is built.
Mulch has bacteria that consume necessary nitrogen from the soil, plants, and garden. The bacteria feed on the woodchips and aid in the decomposition process. However, once the bacteria die, the nitrogen is released back into the earth, at potentially higher levels.
When plants suffer a lack of nitrogen, their leaves turn yellow. If it appears that plants are lacking in nitrogen, add fertilizer to the soil. Ammonium sulfate is an inorganic salt used as a fertilizer; this is the most concentrated nitrogen source.
Rate of Decomposition Determined by Climate
Decompositions occur more rapidly in the tropical climate. Frequent incidents of rainstorms and unyielding wind will accelerate the decay and deterioration. Mulch efficacy is also dependent on the time of year and season.
Mulch provides warmth during the cooler spring seasons to seedlings and retains warm air otherwise lost during the night. In winter, it slows the soil freezing and prevents a phenomenon called frost heaving. Frost heaving is the upward swelling of soil.
The leafy matter of mulch has microbiomes, and extensive communication between biomes is determined by the different aspects of the surrounding environment. Factors include moisture content in the atmosphere and soil, the temperature, the climate, and the soil’s alkaline level.
The Carbon-Nitrogen Ratio of Wood in Mulch
The tree’s age is relevant when it’s put through a woodchipper. If a tree has completed its life cycle, and the material has been dead for a while, there will be no green leafy material or coniferous matter. What remains is predominately carbon material that has lost a considerable level of nitrogen components.
Young trees run through a woodchipper have more significant nitrogen relative to carbon. The carbon-nitrogen ratio affects the thermophilic- heat thriving bacteria that populate the mulch on the surface area of dead plant matter.
Wood mulch could be subjected to high temperatures because of thermophilic-heat-loving bacteria and dry out the mulch. There may be the colonization of specific water repellent fungi- hyphae, which form thread-like structures that prevent the required amount of water in the soil.
The Rate of Decomposition Due to the Size of Mulch Pieces
The size of the mulch pieces is another feature that affects decomposition. The smaller the components, the greater the surface area of the actual mulch the more rapid the biological elements will break down and decompose the mulch.
Smaller, shredded mulch is vulnerable to the physical elements, and both wind and rain will have an undeniable impact. The mulch will lose its structure- its protective, insulative capacity. Added, the finer the size of the particles, the thicker the mulch applied. Thick mulch promotes weed growth.
Consolidation is also an integral feature of decomposition. The compression and size of each particle contribute to the amount of air within the mulch. Oddly shaped and individualized pieces ensure increased availability of air. The atmosphere (oxygen) is essential to assist the fueling of decomposition.
Oxygen Is Integral to Mulch Decomposition
To increase the decomposition rate, rake and turn over the mulch every few months to aerate and ensure an adequate level of oxygen throughout the mulch. Oxygen is vital for cellar respiration and, therefore, plant growth. Unhindered airflow permits necessary air to reach roots and fuel critical bacteria.
To add oxygen to mulch, include plant matter and animal manure. The organic material used in mulch and compost would ideally include brown (dead plant debris, manure, twigs) and green (fruit rinds, lawn clippings, conifer pieces). Brown matter contributes carbon, and green material provides nitrogen.
Essential Food Elements, Recipes, and Mulch
Another aspect that assists in increasing the rate of decomposition includes baking sugar. The sugars feed the microbes and will accelerate the decomposition process. Also, beer is full of enzymes and proteins to grant that extra shot of nitrogen. There are varied recipes available to guide the correct formation of mulch required.
Mulch Is Essential for Plant Growth
Organic mulch decomposes into nutrient-rich organic matter. The material is thick, dark, and appears rich. Upon closer inspection of soil, you’ll discover that only 10% comprises fuel-providing plant matter. The remainder of 90% of the earth is minute particles of rocks and sand, which doesn’t assist in plant growth.
Mulch works as an insulator and provides a protective cover that shields the soil and delicate plants from the damaging ultraviolet radiation of the sun’s rays. Mulch inhibits weed germination and will enhance soil productivity. Mulch has an abundance of nutrients and microorganisms that support life, such as earthworms.
Earthworms enhance the soil’s level of nutrition; their castings are the result of digested plant debris. Nitrogen is abundant in their castings and the dead matter of their bodies.
Earthworms also improve drainage through the vast network of their constant tunneling, which aerates the soil. Earthworms enhance the soil structure, as their casts store water and promote stability.
Guidelines for Arranging Mulch
Keep track of the initial installation of the first layering of the mulch. Take note of the first signs of decomposition, including the dampness of the mulch. Water-logged mulch could be an instance of improper drainage. For best results from mulch, ensure there are one to three inches of mulch.
Allow an acceptable degree of space between the base of the plants and the mulch, about several inches. Mulch arranged directly on the crown or bottom of the plant will cultivate diseases like crown rot. Avoid a volcano-shaped mulch build-up around the tree’s base.
Don’t place successive layers too thickly. Layer approximately two to four inches throughout the landscape. Apply fine mulch two inches deep and course mulch (that consists of bark and wood chips) four inches thick.
Applying thick layers of mulch isn’t advisable as it will obstruct the necessary air required by the plant and microbes. Mulch that has wood could harbor termites. Therefore, don’t place wood-intensive mulch close to buildings or structures.
Burying mulch under the top layer of soil has varying different effects on its decomposition. For example, it will take longer to decompose as it isn’t exposed to oxygen. Oxygen-deprived mulch will generate dangerous acetic acid. Mulch will not stop weed germination if buried under the topsoil.
Final Thoughts
Organic mulch is guaranteed to decompose, as all living matter has a host of microbes whose interaction contributes to decay. Mulch is essential to the upkeep and maintenance of topsoil. It has numerous benefits that include stabilizing the temperature and retaining the moisture content of the soil.
Factors that increase decomposition include adding nitrogen, beer, and baking sugar to feed microbes. Be mindful of the size of the mulch and its application of it on your piece of land. Oxygen is essential to the efficacy of mulch and the role it plays in sustaining the topsoil.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.