The Earthworm—A Gardener's Ally in the Soil

Earthworm species are found all over the world except in arid and arctic regions of the world, with over 2,200 known species. As they burrow through the soil in any of these regions, they eat the organic matter in it.

They excrete a rich organic material known as worm castings.

You'll often see these castings outside a small hole in the ground.

There are enough earthworms burrowing through good soil to produce from 7 to 18 tons of castings annually on each acre of land.

How many is enough? Current estimates put the number at 1,750,000 worms per acre of good soil, to as few as 250,000 per acre in poor soils. That's 6-40 earthworms per square foot of garden.

Earthworms are hermaphroditic. Having both sex features, when two worms mate, they fertilize each other.

Eggs with tough shells (they're actually cocoons) are laid. The young hatch as miniature adults, and mature within a year.

Depending on where you live, you soils may also have earthworms that reproduce without a mate (basically a cloning process called parthenogenesis).

While the average lifespan is 4 to 8 years, most of the species you'll find in your gardens live much shorter lives, usually about 1 to 2 years.

Earthworms range in length from 1 inch (2.5 cm) to the 11 foot (360 cm) worms of the tropics. The common American and European types are up to 10 inches (25 cm) long, with about 150 segments.

Night crawlers (also called dew worms, angleworms (they're used as fishing bait) and rainworms) are one species of earthworm.

The worm used for composting is the red wiggler. Found naturally in many organic refuse piles, dozens of this small worm are sold in a package for you to use to reduce your organic waste into garden fertilizer.

Earthworms are sensitive to light, touch, vibration, and chemicals. The best way to keep worms in your soil is to avoid the use of chemical fertilizers and pesticides, and keep the soil full of organic matter. Worms

Frequently Asked Questions

1. Q. Are earthworms nocturnal?
   A. They're sensitive to light, which is why they surface at night or on cloudy days only.
2. Q. What are the environmental uses of earthworms?
   A. Their castings feed the soil and improve its texture and tilth. They also aerate the soil by burrowing through it.
3. Q. How do they compost?
   A. Earthworms eat organic matter, which they grind up in the gizzard and excrete as castings. Learn more about worm composting, also called vermicomposting.

If this page was valuable for you, please share your new knowledge. Click Like...