Last week’s article on vegan compost mentioned how earthworms help “drought-proof” a garden by tunneling through the soil. This week, we’re exploring the role earthworms play as living compost bins.
Humankind remembers that Charles Darwin introduced us to the theory of evolution with his On the Origin of Species. However, hardly anyone remembers his final, best-selling work, The Formation of Vegetable Mould Through the Action of Worms.
But veganic gardeners can share Charles Darwin’s appreciation of their role in feeding the world! It was an appreciation he expressed unreservedly:
“It may be doubted whether there are many other animals which have… so important a part in… the world, as these lowly… creatures.”
Earthworms are Earth Movers
Even before the first plow turned a piece of sod, earthworms were tunneling. But they weren’t tunneling alone!
This metareview of more than 50 studies of earthworm’s digestive processes explains:
“The participation of microorganisms within the digestive tracts of earthworms is of great importance given that a lot of these are involved in the degradation of organic matter …“
These microorganisms transform the soil and organic matter passing through their intestines into excrement, aka worm castings or vermicompost.
Earthworms are Living Compost Bins
Yes, their intestines function as living compost bins!
Vermicompost is loaded with humus. Healthy soil typically contains 2 percent humus, which traps up to 90 percent of its own weight in water (the earthworms’ “drought-proofing ” phenomenon).
Humus also has humic acid, which helps gardeners in a variety of ways.
- increases the soil’s microbial activity.
- encourages strong root systems.
- improves nutrient availability.
- slows the growth of harmful fungi.
and stimulates natural plant-growth regulators.
Vermicompost holds beneficial mycorrhizal fungi. They latch on to the plants’ roots and help them absorb water and soil nutrients. According to the Penn State Extension, vermicompost’s available nitrogen, phosphorous, and potassium exceed those of the surrounding soil.
Those are the three essential macro ingredients in every N-P-K fertilizer. However, you don’t need to worry that natural vermicompost will burn your plant’s roots as chemical N-P-K fertilizers can.
But there’s even more!
Earthworms Manufacture Essential Minerals
The list of trace minerals in vermicompost reads like the nutrient label on a broad-spectrum mineral supplement:
Our fruits and veggies are no more nutritious than the soil they grow in. Earthworms have an unmatched talent for replenishing soil nutrients. And by sequestering carbon in the soil while feeding oxygen-producing plants, they may even be battling climate change!
Even earthworm slime has its virtues! Yes, they are slimy, but the slime helps them tunnel. It also has nitrogen and glues soil particles into clumps called aggregates.
Aggregates serve as storage vessels, holding organic matter, air, water, nutrients, and microbes. The more aggregates soil has, the less likely it is to be blown or washed away.
How to Help Them Help You
The best thing you can do for your earthworms (and your entire soil food web) is to go no-till. Replace your shovels, spade, or rototiller with a narrow-tined digging fork. Punch holes in the soil instead of turning it over.
You’ll still disturb the upper few inches when planting, weeding, or picking your flowers and crops. But you’ll leave the soil food web, including the worms, intact.
Even if your pitchfork stabs one or two earthworms, the head of the worm may be able to grow a new tail-end.
We should be doing everything possible to create healthy soil biodiversity, and earthworms are at the heart of a thriving underground ecosystem. Growing our gardens in soil teeming with worm life should be every gardener’s goal.