Natural treatments for illness typically revolve around eliminating “the bad” (e.g. toxins) and boosting or amplifying “the good” (e.g. wellness). Similarly, natural treatments for landscapes, such as compost, can help simultaneously eliminate the bad and boost or amplify the good. The following examples illustrate the potential positive impacts of compost.
Compost can help eliminate the bad
Directly, compost can help filter out pollutants. In a process known as bioremediation, microorganisms capture or break down contaminants in water or soil. Did you know that in one teaspoon of living soil there are 100 million to 1 billion bacteria? These bacteria act like an enormous, microscopic, hungry army that metabolizes surrounding materials. Indeed, the active bacteria in compost have been shown to effectively transform many types of contaminants – including chlorinated and non-chlorinated hydrocarbons, wood-preserving chemicals, solvents, heavy metals, pesticides, petroleum products, and even explosives! – into humus (pronounced HU-mus, a bit different from the garbonzo-based dip known as hummus) and inert byproducts.
Indirectly, compost also supports plants that perform bioremediation services. For example, bracken ferns are able to grow in even the most polluted soils, and draw heavy metals out of the earth and into their tissues. Violets (Rinorea Niccolifera) are another example of a toxic-sucking plant: they consume nickel. Compost, applied as a soil amendment, can help these plants grow and persevere.
Compost can help boost the good
Almost every introduction to compost mentions that it improves the physical, chemical and biological properties of soil. I like to provide comparable descriptions of a human’s lifestyle in order to illustrate how compost helps soil – and the plants in that soil – thrive.
Physical properties: Similar to if you regularly stretched, lifted weights, and raised your heartbeat through cardiovascular exercise, compost helps improve soil structure. It has magical-like shape-shifting properties that adapt to meet the needs of the host soil. For example, if your soil is sandy, compost will add organic matter and increase its moisture retention. Alternatively, if your soil has high clay content, compost will increase its percolation and ability to drain. Quality soils allow water to drain through, retain moisture, and promote strong root growth, plant growth, and harvestable crops. Soil is the stage where life happens every day – every plant and animal is an actor.
Chemical properties: Similar to if you ate a healthy diet, compost increases the ability of roots to uptake nutrients. It replenishes and stores organic nutrients. Almost more importantly, compost also makes nutrients available to roots and plants. It is truly the first and best form of slow-release fertilizer. In a curious twist of nature, some minerals, such as phosphorus, cannot be absorbed in their raw form by roots. That’s where compost fits in: the millions of microbes in compost uptake the phosphorus, and then poop out tiny excrement (which is really food for some other life form). Roots of plants can absorb the excrement of those phosphorus- and other nutrient-consuming microbes. Plant roots respond by producing “exudates” that feed the microbes. It’s a win-win. The same story unfolds for nitrogen, potassium, and all the micronutrients needed for healthy soil and plants. In sum, you need both the nutrients and the microbial activity for proper absorption.
Biological properties: Similar to if you surrounded yourself with a robust community of diverse individuals that supported your growth, compost is like a mini ecosystem party. The billions of microorganisms in each teaspoon of compost mentioned earlier in this article help regulate the soil, suppress disease, and discourage pests. It’s a small, wild world teeming with life, and compost helps the good guys keep playing all season long. One scientist found the soil in a corn field had seven trophic levels where one organism was consumed by a slightly larger one – at seven levels. Think of the primal forest or savannah on the head of a pin (or a single crumb of soil).
While compost is a natural and gentle additive to your garden and can be used regularly to enrich your soil, I feel the need to pause for a moment here and note that there can be too much of a good thing, even with compost. The mineral content can be too much and the drainage and air exchange might be low. You don’t want to plant directly into compost. Soil is a planting medium; compost is a soil amendment. For most plants a mixture of 80% soil and 20% compost works well.
The results of applying compost are simple: compost helps create healthy soil, which helps spur healthy roots, which helps grow healthy plants! At the same time the benefits of compost are quite complex and nearly endless. Key highlights of compost application include that it:
- Adds organic material and nutrients to soil
- Enhances the water holding capacity of soil
- Increases the biological activity in soil
- Reduces erosion and water run-off
- Loosens clay soils for better root development
- Retains moisture in sandy soils so plants need less water
- Reduces the need for fertilizers and pesticides
Now that you are inspired to splice compost into your natural life to either eliminate bad or boost good, try the following tips:
For gardens, apply a 1 inch – 3 inch layer of compost and mix into the top several inches of your existing soil.
For lawns, spread a thin layer of finely screened compost, up to a depth of ¼-1/2 inches, just covering the surface.
The fall is a wonderful time to apply compost because it has the winter season to settle down into the soil during rainy and snowy months. Come spring, your landscape’s roots will be ready to grow. Now get out there and give your garden a natural boost.
Meredith Sorensen is the Director of Communication for Harvest, a company creating a more sustainable future by turning organic materials into locally consumed products that are good for the environment. Harvest New England provides top quality soils, mulches and custom blends in Connecticut in our Fairfield, Farmington, Ellington, and Wallingford locations, and can be found at: http://www.harvestpower.com/ne