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6 Benefits of Adding Organic Matter To Your Garden Soil

An overview of the six ways that organic matter can benefit your garden soil. 

Quick question: how has your garden soil been looking lately?

If you've ever thrown a passing glance at a gardening magazine or almanac, you'll know that the key to a successful garden lies right under your feet. Improving soil quality is almost always at the top of a gardener's to-do list. That's because healthy soil equals healthy plants.

Next question: how, then, do you improve the quality of your soil? The answer is, surprisingly, very near at hand: the contents of your kitchen garbage bin.

This article is going to walk you through all the ways that your household food waste can actually nourish your garden soil. Time to get our hands dirty!

 

Up to 50% of your household waste is composed of uneaten food. Food waste which decomposes anaerobically (no air) in the landfill generates methane gas, which is ~25X worse for the environment than CO2. However, if handled correctly, food waste can actually do wonders for both the environment and your garden soil.

Soil that is rich in organic matter (also called biomass, humus or compost) has the best chemical and structural composition to allow your plants to thrive. Have you ever wondered why the soil in forests is so rich and dark? That's because the forest floor is saturated with leaf litter, animal waste and other woodsy materials - organic matter. This naturally occurring organic matter will, over time, decompose aerobically, mulching down into the soil beneath.

So - what does organic matter actually do for your plants?

1) Adds nutrients

Organic matter adds a host of nutrients to the soil: one of these is nitrogen, a key building block of healthy soil. With every percentage increment of organic matter, 20-30 pounds of nitrogen is released into the soil. One of the three most important macronutrients required for healthy plant growth, nitrogen supports stem development and the production of chlorophyll.

Higher percentages of organic matter also increase the amounts of sulphur and phosphorus pentoxide (P2O5) in soil. These compounds help plants photosynthesize light and carbon dioxide from the atmosphere, a key process of metabolizing starches and sugars, which plants use to generate energy.

Organic matter also makes nutrients available to the macro-and micro-organisms living in your garden soil. Aerobic bacteria (microbes) consume and process organic matter, contributing a host of crucial nutrients to your plant roots. Worms and insects likewise feed on decaying organic matter, further breaking down the biomass into smaller, more soluble particles.

2) Balances soil pH

pH - or the measure of acidity/alkalinity - is an important variable in soil health.

 

FYI

A "high" pH (above 7, which is neutral) means that the soil is alkaline (or basic).

A "low" pH (below 7) means that the soil is acidic.

 

When a soil is neutral-to-slightly-acid, it can more easily dissolve nutrients and make these available to plants. For example: soils with a pH of 6.5 can make hard-to-get macronutrient phosphorus available to plants.

More alkaline soils have a harder time dissolving these nutrients. However, too much acidity, and the wrong kinds of compounds can become available to plant roots: these include soluble aluminum, manganese and iron.

The soil's natural acidity or alkalinity fluctuate over time; synthetic nitrogen fertilizers, for example, are known to acidify soil. While some plants actually thrive in more alkaline or acidic environments respectively, your soil should be as close to neutral as possible (between 6 and 7 on a pH scale).

 

Did you know?

The pH scale was invented at the Carlsberg Beer factory by Søren Sørenson in the attempts to craft the perfect beer.

 

Perfectly cured compost (or organic matter that has already decomposed) is almost always within this ideal range, making it the perfect addition to soil veering toward either end of the spectrum.

Soils with a higher pH (alkaline) can likewise be acidified by adding organic matter (compost or otherwise), as, when organic matter decomposes, it releases gentle acids into the soil.

Essentially, organic matter acts as a pH buffer in the soil: by generating its own acids, it helps make nutrients available to plants. When soil is too acid, adding organic matter helps to absorb and make use of excess acidic compounds, such as hydrogen.

3) Protects soil from harmful compounds

Organic matter significantly reduces the impact of harmful elements and pesticides in soils.

Soil contains many different compounds: some of them beneficial to plants, others less so. One of these, aluminum should pose little threat to plants. However, if soils become more acidic, aluminium becomes soluble which can damage plant roots. Incorporating organic matter into acidic soil causes metals to bind, mitigating their negative effects on plants.

Remarkably, organic matter has a similar effect on pesticides. The organic particles bind to these toxins and prevent them from leaching into groundwater. By keeping the chemicals localized, the pesticides gradually diffuse to a point where they are harmless and consumable for microorganisms.

4) Increases aeration

Did you know that healthy soil is roughly 25% air?

Properly aerated soil allows the soil and all the living creatures beneath its surface to "breathe": when the soil is not densely clumped together, oxygen can pass between the soil particles.

A vital source of nitrogen for plants, beneficial life forms such as earthworms, insects, and fungi, require ample oxygen to survive. These insects consume organic materials, processing them so that their waste (worm poop, for example) adds vital vitamins, hormones and compounds to the soil. These elements support plant health, and protect them from diseases.

Organic matter makes the soil more breathable by adding texture to denser, clayish soils. Biomass can also help "tighten up" sandier soils, by providing an absorbant layer that can trap and retain water.

 

Pro Tip:

Frequently till organic matter throughout your garden in drier conditions, as excess moisture dissolves nutrients prematurely.

 

5) Improves water retention

Much like air, healthy soil contains 25% water. Adding organic mass creates a healthy balance of small and large particles, which regulate irrigation. Additionally, organic matter keeps up to 90% of its weight in moisture, thereby storing water for use during times of drought.

6) Reduces erosion

Adding biomass to soil improves its ability to bind together, a state referred to as soil structure aggregation. Experts predict that increasing soil’s organic mass by 1-3% can reduce erosion by nearly one third, while providing better filtration of water throughout your garden.

A modern alternative to a food composter that improves your garden’s long-term health

The FoodCycler continually provides odourless, nutrient-rich organic matter, which, as we've seen, improves the quality of soil in many ways:

  • Provides nutrients for plants & microorganisms
  • Reduces the presence of harmful compounds
  • Better oxidation
  • Balances pH levels
  • Increased water retention
  • Reduced erosion
  • Improved soil structure
  • Retention of beneficial compounds

The FoodCycler transforms household food waste into a nutrient-dense biomass, in hours. Because food waste is a never-ending stream - 36% of food waste is inedible (such as stems and peels) - your garden will always have a source of enriching organic matter.

Are you unsure how to garden with your FoodCycler organic matter? Check out our blog explaining five easy ways to add FoodCycler fertilizer to your garden!