Why Earthworms are Worth Keeping Around
Most homeowners will do anything to keep pests and other insects off their lawn, but earthworms are different. Through their ability to break up soil and thatch and form nutrients, earthworms are one type of insect worth keeping around for a healthy lawn.
For most soil types, earthworms are essential for its health. A healthy soil is indicated through its ability to distribute water and nutrients to the roots of plants and make them grow. Earthworms naturally tunnel through the soil to break it up, creating space for air and water to flow through. This is why soil containing earthworms does not become compact or hardened.
Earthworms also consume thatch for food, which is great for keeping thatch problems down to a minimum. Thatch, which are rough patches of grass, make it difficult for water and fertilizer to penetrate the soil and reach the roots of plants. Insects and other lawn diseases can also establish havens around thatch, making earthworms even more vital to keep around.
In addition to getting rid of thatch and disease, earthworms also consume other organic materials, such as leaves and dead plants. This allows them to produce castings, or feces, that they leave behind in the soil, creating nutrient-rich fertilizer that keeps the soil healthy and plants growing. It also means dead leaves on your lawn will decompose at a faster rate.
Some homeowners will try worm composting, which involves adding compost to a container of earthworms to consume before releasing them into the soil. This also works, but it can be messier (and smellier) to deal with.
Having earthworms auto-fertilize the soil is also cost beneficial. Worm castings contain 50% organic matter and 11 trace minerals, which can be difficult to find and expensive to purchase. Fertilizer in general, especially if you need to use it more than once a year, can build quite the expense. Earthworms cost significantly less and you can save yourself from spreading smelly fertilizer on your own.
Earthworms also get rid of disease and soil pests. Soil with high earthworm populations have shown to have low numbers of nematodes, which are pests that live in the soil and pose harm to plants as they consume the roots. A decent population of ants would be around 25 per cubic feet of soil.
In order to maintain a steady population of earthworms, limit the amount of chemicals that are used. This means chemical-based fertilizers and weed killers will need to be kept at minimum in order for earthworms to thrive. Also, rake a thin layer of compost across the top of the soil in the spring. This gives the worms an immediate source of food to start with before burrowing into the ground.
Despite their unappealing looks, earthworms should not be considered a pest! Their populations typically do not go out of control and even in large numbers they can prove highly beneficial to improving the soil quality.
Be sure to verify that the worms in your yard are actually earthworms. There are some invasive species of worms that can harm the soil by consuming the soil nutrients and plant roots. Contact a pest control service or lawn care company to ensure that only beneficial earthworms exist in your yard.