Lawn worms – enemy or friend?

5 Minute(s) read

Although worms may seem like they could damage your lawn, this couldn’t be further from the truth. Earthworms, specifically, are fantastic for the health of your lawn. They work away busily beneath the surface, providing the soil with a good balance of organic material.

The presence of earthworms is evidence that you have healthy soil. In fact, it is a concern if worms are not in your soil, as this likely indicates that the soil is lacking in nutrients.

What are the benefits of worms in my lawn?

Worms, those seemingly humble creatures that dwell beneath the soil, offer a multitude of benefits to lawns. Their presence can greatly contribute to the overall health and vitality of a lawn ecosystem. Some benefits include: 

Worms can break down thatch  

Worms play a crucial role in breaking down thatch in lawns through a process called vermicomposting. Thatch is the layer of dead grass, roots, and other organic debris that accumulates on the surface of the soil. Here's how earthworm activity can help break down the thatch layer:

1. Consumption: worms feed on organic matter, including thatch. They consume the thatch and break it down into smaller particles through their digestive system.
2. Mechanical action: as worms move through the soil, they burrow and create tunnels. This burrowing activity helps to aerate the soil and improves drainage. Worms bring the thatch material into their burrows, where it becomes mixed with the soil.
3. Digestion and excretion: once the worms consume the thatch, the organic matter undergoes digestion in their digestive tract. The organic materials are broken down by enzymes and microorganisms present in the worms' gut. The worms excrete casts, which are nutrient-rich droppings containing beneficial microorganisms.
4. Nutrient release: the excreted casts are deposited in the soil, enriching it with essential nutrients and organic matter. These nutrients are then made available for the surrounding plants, promoting their growth and soil fertility.
5. Accelerated decomposition: worms' feeding and digestion activities speed up the decomposition process of thatch. The breakdown of thatch by worms helps to prevent its accumulation and allows it to be recycled back into the soil profile more quickly.

Worms can aerate the soil 

Worms are excellent soil aerators due to their burrowing activities. By burrowing, loosening the soil surface, and incorporating organic matter, worms improve soil aeration. Adequate soil aeration allows for better root development, enhances nutrient uptake by plants, improves water infiltration and drainage, and creates a healthier environment for beneficial soil organisms.  

Worms create usable nitrogen in the soil 

Worms contribute to the creation of usable nitrogen in the soil through their feeding and digestive processes. The combined processes of worm digestion, castings deposition, and microbial activity contribute to the conversion of organic nitrogen into plant-available forms, enriching the soil with usable nitrogen. This nitrogen availability supports plant growth, chlorophyll production, and overall plant health.

Worms can decompose soil and liberate nutrients  

Worms play a significant role in decomposing soil and liberating nutrients through their feeding and digestive activities. By consuming organic matter, mechanically breaking it down, and facilitating microbial interactions, worms accelerate the decomposition process in the soil. Through their castings, they enrich the soil with valuable nutrients and beneficial microorganisms, creating a fertile environment that promotes plant growth and a healthy lawn.

Why do people think worms are a problem in lawns?

People often feel concerned when worms surface during spring and autumn. During these seasons in Melbourne, the moisture content in the soil increases. This makes it hard for the earthworms to breathe, so they rise to the surface, where they leave ‘castings.’ Also known as mud balls, castings are small mounds of worm excrement. 

This digested organic matter is highly beneficial for your lawn. So why do some people seem so concerned by it? It’s purely an aesthetic issue – many are turned off by the messy appearance of earthworm castings on their lawn. However, if you can look past the moderately bumpy turf, these earthworms keep your lawn healthy and encourage plant growth, and they can be used as a natural fertilizer. 

What can I do about worm castings?

When the castings are dry, you can rake the lawn to distribute them. This is essentially like spreading free organic fertiliser, as the castings will settle down into the roots and provide nutrition for your lawn. You can also reduce the appearance of castings by mowing your lawn slightly higher.

So, though it may not be the cutest species in your garden, the humble earthworm is most certainly a friend to your lawn. Next time you see them in your soil, smile and give yourself a pat on the back for supplying the right nutrients for both them and your lawn to live happily ever after.

How can I encourage earthworms into my lawn?

To encourage worms to break down thatch and fertilise your lawn, you can adopt practices that promote a worm-friendly environment. For example, you can: 

• Avoid excessive use of chemical fertilisers, pesticides, and herbicides, as these can harm worms and other beneficial organisms.
• Ensure proper soil moisture by watering deeply but infrequently. Overwatering or waterlogged soil can negatively affect worm populations.
• Maintain a slightly acidic soil pH, ideally between 6 and 7, which is favourable for worms.
• Use organic amendments like compost and mulch to provide additional food sources for worms and improve the overall soil health.
• Avoid compacting the soil by minimising heavy foot traffic or using heavy machinery on the lawn. Compacted soil restricts worm movement and activity.

By creating a favourable habitat and avoiding practices that harm worms, you can encourage their presence and enhance their ability to break down thatch naturally in your lawn.

If you have any further questions about earthworms in your lawn or about general lawn maintenance, contact our friendly staff at Lilydale Instant Lawn today.