How to Attract Earthworms to Your Garden

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A lot of people look at earthworms in disgust; their sleek, writhing bodies aren’t exactly the most adorable thing in nature but looks aside, earthworms serve an important purpose. In fact, if you want a healthy garden then they’re an essential part of the ecosystem. But how do you attract them? Let’s find out.

How Earthworms Benefit Soil & Plants

Earthworms are crucial to a healthy garden, and they have a variety of benefits. By attracting these wriggly creatures to your yard, both your plants and soil will thrive.

Not only do earthworms improve the structure and drainage of the soil, but they also improve its fertility through their excrement.

Improves Soil Fertility

Fertile soil is vital for healthy plants. Soil that’s not filled with the correct nutrients won’t provide ‘food’ for your plants, which will then struggle to survive. While there are lots of chemical fertilizers on the market, these can be damaging to the environment, so finding organic methods is super important.

A prime example of this is earthworms. When they poop, worms release what is known as a casting, and these castings are bursting with nutrients that plants love. Not only do the worm castings contain more than 1000 times the amount of beneficial bacteria than regular soil but they’re also packed with nitrogen and phosphorus, which is essential to plant health and growth.

While attracting earthworms to your garden is the best way to get plenty of castings, it’s also possible to buy bags of worm castings to further enhance your soil.

Better Soil Drainage

Well-draining soil is another key factor in having healthy plants. When the soil is dense and holds onto water, this can damage the plant roots and essentially drown them. While we know that plants need water to survive, you can have too much of a good thing.

Regularly aerating and turning your soil is a great way to promote good drainage, but if you want to lessen your workload, earthworms will help.

This is because, as the worms move about in the soil, they create channels and tunnels through which water can flow. In fact, studies have shown that soil with worms is up to 90% more effective at draining water than soil without worms.

Improves Soil Structure

I’ve just discussed the importance of aerating your soil, a process crucial not only for drainage but also because the soil structure influences how effectively plant roots can establish themselves. In very dense or compacted soil, roots may encounter difficulty penetrating and may remain more shallow.

Deep roots provide the plant with a strong anchor, enabling it to efficiently absorb water and nutrients from the soil.

The presence of earthworms means improved soil structure as again, their channels and tunnels keep the soil moving and loose. Not only this, but these tunnels create little pockets of air and, just like us, plants need oxygen at their roots.

Helps to Break Down Organic Material

Organic material is what helps to keep soil healthy and full of nutrients. This can include insect corpses, animal droppings, bark, and other such materials.

However, they only provide those essential nutrients when they are broken down, as this process is what releases all that goodness.

Having earthworms in the soil aids in speeding up this process. Again, this comes as a result of how the worms move through the soil, distributing and breaking down organic materials as they tunnel around.

In addition to this, earthworms actually eat organic matter and, when this is broken down, bacteria and microscopic life feed on the results, further breaking down the materials and releasing the nutrients.

Ideal Soil Conditions for Earthworms

If you’re looking to attract earthworms to your garden then you must create the ideal conditions for them. You wouldn’t move into a home that didn’t have everything you need and neither will a worm.

One of the first and most important things to consider is the type and quality of the soil. If worms are going to come then the acidity should be spot on and, in this case, it should sit somewhere between 6.0 and 7.5. This ensures that it’s neither too acidic nor too alkaline, but it’s also imperative that the soil contains enough magnesium and calcium to benefit the worms’ health.

You can buy soil testing kits that allow you to assess the pH and nutrients within the soil. Off the back of these results, you can alter the pH of the soil. For example, if it’s too acidic, try adding some lime. Alternatively, for soil that’s too alkaline, you can add compost or manure to increase the acidity.

It’s also important to consider the texture of the soil. Earthworms have a tough time burrowing into compacted soil and prefer loamy, loose soils that contain plenty of organic matter. Be mindful that sandy soil is problematic for worms as, even when wet, it drains and dries out incredibly quickly.

Tips on Creating an Earthworm-Friendly Garden

Considering the quality of your soil is a great place to start when it comes to attracting earthworms, but it’s not the only thing to keep in mind. Your aim here is to create a haven for worms who will want to stay in your garden. As a result, they’ll reward your hospitality by ensuring the health of your plants. It’s a win for you and your wiggly little guests.

1. Avoid Pesticides & Chemical Fertilizers

I won’t sugar coat it, pests can be a real problem in the garden. But how you deal with them can affect the overall health of your garden and plants.

Chemical pesticides and other products like fertilizers might be effective but they’re not environmentally friendly. With so many organic methods out there, there’s really no excuse for using chemicals as a modern gardener.

Whether you’re looking to improve the health of your lawn or rid your prized crops of aphids and spider mites, choosing natural methods will be both effective and safe. As a result of this, beneficial creatures like worms, and others such as pollinators, will be more attracted to your garden. Once they’re there, they’ll do all the hard work in place of chemicals.

For example, using compost or fish emulsion is an excellent way of adding nutrients to the soil while introducing natural predators like ladybugs will take care of any pest problems.

The reason that this is so important is that chemical pesticides and fertilizers can be absorbed directly into the worms’ skin and cause burns or even death. Even if they survive, worms born in chemical-ridden areas have been shown to have reduced growth and problems with their reproductive health.

2. Improve Soil Quality

Earthworms will only be attracted to soil that contains a good amount of organic matter, as this is what they feed on. So, improving the soil quality and ensuring lots of nutrients for the worms is a great way to draw them to your garden.

As I mentioned earlier, testing the soil pH is a vital step as this allows you to assess and amend the soil as required. Adding compost to your soil is a fantastic way to improve its quality, and this is something you can make in your garden.

Whether you choose a compost bin or simply a heap, the benefits are the same. You can add things like grass clippings, vegetable peelings, shredded paper, and plant prunings to your compost pile. After this, it’s simply a case of letting nature take its course. Just make sure that the pile has plenty of air (so turn it regularly) and water. The materials will begin to break down, and the resulting compost can then be directly added to your soil.

While it is possible to add dead leaves to your compost heap, it’s also recommended to allow them to decompose on the ground. Avoid raking up fallen leaves and let them rot in place because, as they break down, nutrients are released which the worms can thrive on.

It’s also really important to make sure that your soil doesn’t become compacted, as the worms will struggle to burrow through it. The mere act of walking over your soil can result in compaction so try placing some stepping stones or pathways to avoid this. Furthermore, if it rains, allow the soil to completely dry before walking over it, as wet soil compacts much more easily.

3. Maintain Soil Moisture

Pretty much every living thing on this planet needs water to some degree or another. Yes, there are certain plants and animals that can go for prolonged periods without water, but they need it eventually. This is no different for worms who need a decent amount of water if they’re going to survive.

But this isn’t necessarily for drinking, since worms actually absorb moisture from the soil through their skin in order to remain hydrated. This tells us that moist soil is a must for worms, so be sure to regularly water your garden. In dry periods, you can add a layer of mulch to the soil to prevent the water from evaporating too quickly. Things like straw and wood chippings are ideal for this.

However, you do need to be careful not to add too much water because this can cause the soil to become waterlogged as this can be damaging to the worms. While it is reported that worms can survive for days in waterlogged soil, if there’s enough oxygen, there’s still the possibility of them drowning, so it’s best to avoid this situation. 

4. Provide a Variety of Microhabitats

When we talk about earthworms, we aren’t just referring to one creature; in fact, there are more than 7000 different species of earthworms, and you want to attract as many as possible. 

But in order to do this, you need to ensure suitable habitats for each species, as they all have slightly different needs. For example, some earthworms prefer to hide among leaf litter, while others like the presence of dead wood.

In any case, it’s important to provide plenty of shady spots for the worms as they don’t do well in extreme heat. What’s more, these creatures require a lot of shelter from predators like birds so again, things like mulch and leaf cover are ideal.

5. Reduce Soil Disturbance

Once you have a healthy earthworm population in your garden, the last thing you want to do is disturb it. Tilling may be a common gardening practice, but it can be very damaging to the worms’ burrows and even cause harm to individuals. Therefore, it is recommended to use no-till gardening methods to reduce soil disturbance.

Keeping the soil covered is a great way to reduce the need for digging and tilling. This can be done through the use of mulch or cover plants.

When the soil is healthy like this, it will increase the activity of the worms, which will then continue to maintain its structure, further eliminating the need for tilling.

6. Choose Earthworm-Friendly Plants

When looking to attract any form of wildlife to your garden, choosing the right plants is crucial. In the case of earthworms, you’ll want to be looking for plants that root deeply as this ensures the soil naturally breaks up, resulting in organic channels for the worms and reducing their need to burrow. Things like legumes and brassicas are ideal for this.

However, diversity is key so be sure to choose as many worm-friendly plant varieties as possible. The more you have, the more worms will come. Not only this, but good plant diversity helps to attract a plethora of beneficial wildlife such as pest predators, pollinators, and birds.

One thing to be mindful of, however, is the local climate and conditions. Some plants don’t do as well in certain conditions, so choose those that are well-suited to your climate. Native plants are always thought to be the best option.

Common Types of Earthworms

With more than 7000 species of earthworm in the world, it will come as no surprise that many of these are native to North America. In fact, more than 100 types of earthworms can be found here, and they’re super beneficial to your garden. 

Depending on the variety of the earthworm, it may be found in the surface soil or much deeper down (these are known as anecic earthworms.) What’s more, each type of earthworm plays its own vital role in keeping the soil healthy through processes like decomposition and nutrient cycling. See the table below for a more detailed explanation.

Going even further, different types of earthworms will burrow in different directions; some horizontally and some vertically. Those that burrow horizontally are typically found closer to the surface and are less sensitive to activities like tilling. Let’s take a closer look at some of the most common North American species.

Nightcrawler (Lumbricus terrestris)

Nightcrawler is a term given to the common earthworm which is a large species that can grow to around 9.8 inches (25 cm) when fully stretched out. These worms are native to Europe but are now found in many countries where they’re often considered to be a pest.

Nightcrawlers take their name from the fact that they only come to the surface after dark. During the day, they can be found as deep as 4 feet (1.2 meters) below the surface and are an anecic species that thrive on decaying matter and soil.

With their long bodies, and characteristic reddish-brown coloration, nightcrawlers are one of the most well-recognized worm species and will often be seen coming to the surface after heavy rainfall.

Red Worm (Lumbricus rubellus)

While the red worm is native to Europe, it is now widespread in many countries, including North America. These worms grow to around 1 inch (2.5 cm) in length and have a red coloration, as their name suggests.

Red worms can be identified from other similar species thanks to the tail, which may be flattened into a paddle-shape. Worms grow to around 4 to 5 inches (10 to 12.7 cm) in length and are typically found in the upper layers of the soil.

However, while they are common, red worms, sometimes called redhead worms, are considered an invasive species in North America owing to their extreme feeding habits.

Manure Worm (Eisenia fetida)

The manure worm is one of the most common worms used in vermicomposting. This is a composting process whereby worms are added to speed up the decomposition of organic matter. So popular are they for this purpose, and recreational purposes like fishing, that manure worms are actually farmed.

These worms are sometimes called tiger worms or red wigglers, thanks to their reddish-brown coloration. They feed primarily on decaying organic matter like rotting plants and are known to emit a foul-smelling odor when threatened.

Gray Worm (Aporrectodea caliginosa)

The gray worm has banded sections in both gray and pink and typically grows to around 3 inches (7.6 cm) in length. These are topsoil dwelling earthworms that continually make burrows as they rarely use the same ones again, which is not the case with all worm species.

Gray worms are well known for depositing a lot of worm casts, which improve the nutrient content and health of the soil.

While native to Europe, particularly in the United Kingdom, gray worms are now found throughout North America.

Green Worm (Allolobophora chlorotica)

The green worm is an endogeic species found in the top layers of the soil, where they make horizontal burrows. They’re a very common species but quite elusive and rarely come to the surface.

While the name is confusing, the green worm is often more pinkish in color. This term comes from the fact that some individuals have a special type of pigment that causes them to look green.

Interestingly, those that have this green coloration are more often found in wet soil, while their pink counterparts inhabit drier soils.

Pink Soil Worm (Aporrectodea rosea)

Pink soil worms are native to Europe but are now widespread all over the world, including in North America. These worms are one of the smaller species, generally only growing to a maximum of 2 inches (5 cm).

They can be characterized by their pinkish colored head which extends to the male pores. Because of this, the species is sometimes referred to as the rosy tipped worm. Normally, these worms are found in the top 7.9-11.8 inches (20-30 cm) of soil, where their burrowing behaviors create channels for water, air, and nutrients to flow.

Southern Worm (Aporrectodea trapezoides)

The southern worm is sometimes called the purple worm and is found in the top layers of the soil. Its body is typically between 3 and 6 inches (7.6 and 15.2 cm) in length and comes in a gray to brown color.

Frequently Asked Questions