The total weight of earthworms in our country weights more than that of our entire population! This astonishing number hints at the colossal and indispensable work these unseen laborers accomplish.
Let’s dig a bit deeper underground to better understand the crucial role of the earthworm in the garden.
Collectively, earthworms represent 70% of underground animal biomass.
They include nearly 200 species in many countries, and 5000 species throughout the world.
It’s an invertebrate.
An earthworm has neither eyes nor ears.
The earthworm has five hearts.
It’s a hermaphrodite.
A complex body:
Most kinds of earthworm measure between 2 and 12 inches (between 5 and 30 cm). Its elongated body is more complex than it seems.
Rings, tiny hairs and pierced skin replace legs and lungs
It consists of rings covered with tiny hairs that help it move.
Holes present on its skin allow it to breathe, as it has no lungs. Skin is slimy and covered with mucus to prevent it from dehydrating.
At each end of its body is an important ring. The thinner one is the head. The bigger one is the anus.
In the middle of the body, you can see a larger, soft, purplish ring. It contains the worm’s reproductive organs.
Did you know?
If you cut an earthworm between its reproductive ring and anus, it can survive because all its vital organs are contained between reproductive zone and head. Otherwise, it will die. In no case will a worm cut in half regrow, as is sometimes heard.
The earthworm’s body, ring by ring
Most earthworms measure between 2 and 12 inches (5 to 30 cm), and every part of that elongated body does a specific job. Here is how to read a worm from head to anus.
The earthworm’s body, ring by ring
Body part
How to spot it
What it does
Thin end ring (head)
The narrower of the two end rings
Feeds on organic matter, decaying vegetation, bacteria and fungi, never on crops
Bigger end ring (anus)
The thicker of the two end rings
Expels the remains as a fine, rich soil called castings
Purplish middle ring
A larger, soft, purplish band mid-body
Contains the reproductive organs of this hermaphrodite animal
Ringed body wall
Rings covered with tiny hairs
Grips the soil and moves the worm along
Slimy skin
Mucus-covered and pierced with holes
Breathes for the worm, which has no lungs, and stops it drying out
Cut between the reproductive ring and the anus, a worm may survive; cut anywhere else it dies, and it never regrows into two animals.
Role and use of the earthworm
Their presence in the garden indicates that soil quality is good, because an earthworm does not like acidic, sandy, arid, often disturbed (plowed) and poor, bare environments.
An earthworm is a basically a long digestive tube. Its thinnest ring (equivalent to its head) feeds on organic matter, decaying vegetation, bacteria, fungi and protozoa without ever attacking crops.
Its largest ring (anus) expels remains in the form of a fine soil called “castings”.
Worm castings:
Excrements of earthworms contribute to soil enrichment and plant fertilization. They are rich in magnesium, nitrogen, phosphorus, calcium, and potassium. You can see them on lawns as small twists.
You can use this fine and rich soil for repotting plants.
A very productive partner for gardeners:
Burrows reach four metres down, letting rainwater soak in
There are about two hundred earthworms per square meter, burrowing as down to a depth of 6.5 to 12 feet (two to four meters).
By feeding, they recycle organic materials.
Earthworms tirelessly plow, fertilize, and structure soils, actively contributing to bioturbation
By digging tunnels, they allow better penetration of rainwater into the soil.
Attracting earthworms to the garden
Some elements are conducive to the presence of earthworms in the garden.
Dead leaves, manure and cool clay soil bring worms in
Plant debris like dead leaves.
They delight in manure.
Cool, clayish soils.
Renewal and diversity in the crops and flowers planted.
The ideal garden for earthworms must respect the cycle of seasons with its resting periods and thoughtful maintenance. It is important to keep some areas wild and undisturbed.
Contemplate:
“Earthworms dive into soil so as not to fall in love with the stars”. (Yvan Audouard)
Written by Gaspard Lorthiois | Loves helping out, especially when it comes to growing things. Worked in herbal medicine, runs a farm, and dabbles in tech. Master's degree and engineer.
