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What Do Earthworms Eat


What do earthworms eat? Try dirt for starters. That’s not 100% accurate, but basically true. If depends somewhat how one defines dirt. Most of the dirt we come into contact with, especially dirt in our gardens, contains lots of different kinds of matter, including decomposing or decomposed organic matter. It’s the organic matter that the earthworms eat. But it’s all mixed in with whatever else may be in the dirt besides the basic mineral elements.

A good test is to add some organic elements to your garden soil, such as manure, compost, decaying leaves and the like. If you already have earthworms, eventually you’ll find you have quite a few more. Once they find fertile soil, earthworms will settle in and multiply, at times very rapidly. Earthworms love organic matter, which is why we sometimes put odd things like coffee grounds in the soil to attract them (for use as bait).

The Earthworm Is A Friend – Earthworms live beneath our feet and generally out of sight and out of mind. To call someone a worm is a great insult. Probably more so to the worm if it were to overhear the comment. Earthworms are among our unsung heroes. They constantly till the soil, making it richer and of a consistency which is beneficial to the plants in the soil. Earthworms are farmer’s and gardener’s little helpers, and in terms of what they contribute, their presence is invaluable in the world of agriculture.

What Earthworms Eat – Getting back to the question, “what do earthworms eat?”, they do swallow soil or dirt, so in that sense they eat dirt. Dirt is not always the food of choice, but they swallow it as they burrow, extracting nutrients from it in the process. They much prefer organic matter though and delight in a fresh batch of decaying leaves or compost. Worms don’t have teeth, but strong mouth parts, which enable them to take little bites from a decaying leaf, as long as the leaf is soft enough. Most of the other foods they eat, including many types of fungus, they simply suck into their mouths.

What Earthworms Leave Behind – Regardless of what they eat, as is the case with all living things, whatever is not digested will be eliminated as waste. Worm poop, called casings, is odorless and very small, about the size between a period and a pin head, so you don’t have to worry about tracking any into the house. In addition to tilling the soil by burrowing, the earthworm enhances the soil’s nutrient value through its casings, which add valuable nitrogen to the soil, making plants grow bigger and stronger. A garden full of earthworms, and there can be hundreds to thousands of them in an average sized garden plot, means rich soil and healthy plants. Earthworms and plants go together as both like fertile soil to begin with, and like most plants, earthworms require a soil that is somewhat moist.

Types Of Earthworms – There are over 2,000 different kinds of earthworms on this planet, though if you live in the United States you’ll mostly see four types: Red worms, which are the ones most often sold commercially, Night crawlers, which although are not native to North America have long since made themselves at home here, Manure worms, which thrive in soils that are rich in manure, and the common Garden worm, the familiar resident of most flower and vegetable gardens. All of these types are a few inches in length, rarely exceeding a foot, with 3 or 4 inches being the average size. Given good soil conditions, most earthworms can live for several years, up to 8 or 10 in fact, unless predators, like the robin, are prevalent.

What About Very Large Earthworms? – On occasion, you may read or hear about giant earthworms. These are found primarily in South America and Australia. The largest earthworm ever found was 22 feet in length and weighed over a pound. What do earthworms eat to attain such a giant size? As far as we know, dirt.

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