Vermicomposting in worm bins

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There are thousands of different worms in the average backyard. They come in about 2,700 different varieties, and many of these species are rarely seen. Some worms are camouflaged to hide in plain sight, and others live deep underground and come to the surface only when they have to. After it rains, worms are easy to find because they breathe through their skin and are driven up to the surface and often climb onto concrete driveways and sidewalks. It’s easy to collect these worms for a compost bin, but there are important differences between the worm species you will encounter.

The Common European Earthworm (which is also called the nightcrawler) lives deep underground, with vertical burrows that go about 6 feet down. Night crawlers are commonly found in gardens or near compost piles, but this worm is ill-suited for compost bins. The nightcrawler’s scientific name is Lumbricus terrestris, and it is an anecic worm that doesn’t like to stay near the surface. If you put nightcrawlers in a compost bin, they will constantly try to escape through the bottom of the worm bin, and they will die from exhaustion instead of breeding or working the soil. Nightcrawlers are also sometimes called “tiger worms” because they have alternating red and buff stripes – those stripes make Nightcrawlers easy to identify.

For a vermicomposting bin, Red Wigglers are the best type of worm because they prefer to live near the surface. There are two very similar worms that are both called Red Wrigglers: Eisena fetida and Eisena andrei. Both species look very similar, and they can live side by side without any problems. As red wigglers eat organic waste, they blend it with soil in the bin. Compared to the original soil levels, their worm castings contain approximately 40% more humus, 150% more calcium, 300% more magnesium, 500% more nitrogen, 700% more phosphates, and 1100% more potash.

Here’s a pictorial worm guide that you can use to identify species in your garden. There are many endangered species of earthworm, and if you find a rare one, you can really help improve our knowledge of the species!

After you collect red wigglers, put them to work around your house! All it takes is a sheltered bin, scrap paper, some healthy soil, and your food scraps. Shredded paper goes along the bottom of the compost bin – this acts as a fence to keep worms inside and it also buffers to moisture of the bin. Since paper soaks up water, the layer of paper will help maintain a constant level of moisture similar to a wrung out sponge. Add a layer of soil to the shredded paper, and then bury food scraps under the soil. The soil acts like a highway for worms, and it also introduces healthy bacteria that will accelerate the breakdown of vegetable rinds and fruit pulp.

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