Understanding and Controlling Fairy Rings in Lawns and Sports Turf

Fairy rings are a common but often misunderstood turf issue that can frustrate lawn owners, groundskeepers, and sports field managers alike. In this blog we do a dive deep into what causes fairy rings, why they seem to “suddenly appear,” and the best ways to control them.

What Are Fairy Rings?

Fairy rings are caused by soil-dwelling fungi that feed on organic matter (such as thatch) beneath the grass surface. Over time, the fungus grows outward in an expanding circle, producing hydrophobic (water-repelling) chemicals and leaving behind waxy residues on grass blades.

Contrary to popular belief, fairy rings do not directly kill grass. Instead, they create soil conditions that make it difficult for grass to access water, particularly during droughts — leading to brown, dead-looking rings.

Why Are They More Noticeable in Autumn?

In the summer of 2025, many lawns suffered from drought stress. As a result, turf turned yellow or went dormant. When rain returned in late summer and early autumn, most grass rebounded — but the areas affected by fairy rings did not, making the damage suddenly visible.

In addition, autumn often brings fruiting bodies — mushrooms, puffballs, and toadstools — which appear on the ring edges. While some may find them attractive, they can be slippery hazards on sports fields.

The Impact on Sports Turf

Fairy rings are more than just a cosmetic issue for sports turf managers. They can:

• Create uneven grass growth (twice as tall as surrounding grass in some cases).
• Alter surface playability and ball roll speeds.
• Pose safety risks due to slippery fungal growth.

For sports like football, golf, and tennis, this can mean real problems for play quality and athlete safety.

How to Manage and Control Fairy Rings

Here is a multi-step approach to minimizing the impact of fairy rings:

1. Manage Thatch

Fairy rings thrive in thatch layers. Regular scarification and aeration reduce the organic matter they feed on. You can also get the thatch to degrade much quicker with the use of Thatch Degrader, this will feed the microbes that eat thatch after there numbers have been depleted due to Iron been used throughout the season.

2. Maintain Irrigation

Avoid drought stress where possible. Consistent watering helps prevent hydrophobic conditions from becoming severe.

3. Apply Wetting Agents

Products like Clay Drainer or natural Yucca Extract help break down water-repellent soils, improving moisture penetration.

4. Spot Treatments with Lime Sulfur

We also recommend Lime Sulphur, an organic soil sterilant, for severe infestations. It kills fungi without leaving harmful residues and is safer for players compared to long-lasting fungicides.

5. Consider Reseeding

After treatment, reseed affected areas to restore turf cover and play quality.

6. Fungicides (With Caution)

Fungicides can suppress fairy rings, but they are often less effective on soil-borne fungi and can carry environmental drawbacks.

Should Fairy Rings Always Be Removed?

Not necessarily. Fairy rings are part of the soil ecosystem and can even be beneficial when conditions are well-watered. The decision to treat depends on aesthetics, playability, and safety concerns — especially on sports fields.

Final Thoughts

Fairy rings are not a sudden invasion — they’ve been there all along, slowly expanding beneath the soil. Understanding their biology helps turf managers choose the right control strategies, from wetting agents to organic soil sterilants.

By combining cultural practices (thatch control, irrigation) with targeted treatments, you can keep your lawn or sports turf healthy and playable year-round.

Article by Dr Russell Sharp

If you would like to keep up to date with subjects just like this, you can listen to both our podcasts! Links can be found bellow:

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