4 ways to Rid of Mushrooms in Your Lawn

The unusually humid and rainy summer days in Toronto created the perfect conditions for mushrooms to appear. Never coming across the issue before, we were quite surprised to hear three of our clients (who all got their lawns installed on June 10) reporting mushrooms! Since mushrooms were never an issue for us before, we had to understand what is going on, how serious the problem is, and what can be done about it. We have identified 4 ways to get rid of Mushrooms in lawns.

Here’s what we have learned

1. Mushrooms are a good sign of soil fertility.
2. Mushrooms are easy to get rid of.
3. Mushrooms are never more than a temporary issue.
4. Proper lawn maintenance eliminates the possibility of mushrooms.
5. Shady, humid, and moist environments are perfect for mushrooms to grow.

The 4 Ways to Rid of Mushrooms on Your Lawn

1. Reduce watering frequency
2. Mow every 5 -7 days. Be sure to collect the clippings.
3. Apply a mid-summer nitrogen-rich fertilizer
4. Add a 1” inch layer of sand, to improve the drainage ability of the soil.

 The Story with Mushrooms

Mushrooms will only appear when certain conditions are met:

• You have a rich soil, containing “Mycelium” (Triple Mix, peat moss, Grow-Max, and compost are in this category)
• There is a shady, moist, and humid environment.
• Oftentimes, the soil where mushrooms appear does not drain very well, either due to grading issues or reduced drainage abilities.

Mycelium

This is the vegetative part of a fungus. It plays a vital role in decomposing plant material. It is often found in rich soils; composed of compost, aged bark, and peat – it is expected to have Mycelium.

Mycelium is good – this white-looking substance normally wraps around grass roots, and by doing so strengthens them, makes them more resistant to drought and diseases, and encourages the roots to grow deeper.

Mycelium is not infinite – once it is used up, it requires replenishing (like fallen rotting trees, thick layers of dry leaves – think wild forest after a storm). Once it runs out, no mushrooms can be formed.

Mushroom growers are forced to replace their soil with an entirely fresh batch after each growth period in order to continue growing mushrooms.

Everywhere we searched for information, we learned that soil cannot be “contaminated” with mushrooms. Replacing the soil is not a good idea, and is definitely not necessary. Any good soil will contain Mycelium, and it is not the root of the problem (no pun intended). 

How do mushrooms appear?

Mycelium alone is not enough to form mushrooms. For that, you need to create a highly moist, humid, shady, and stable environment.

The Lawn worst hit by Mushrooms had it all:

• The garden was fairly shady
• Upon installing the lawn, it was watered several times a day (as a new lawn normally should)
• In addition to the manual watering, June and July were extremely rainy and humid in Toronto this year.
• The lawn was mowed only once during the first two months, providing a stable environment of long-wet grass blades.
• The grass clippings were left on the ground, adding another layer of moisture and rotting material.

 So, how to make the mushrooms go away?

We were greatly relieved to learn that it is extremely easy to make mushrooms go away:

1. Reduce watering. Before turning a sprinkler on – check the soil. If it is moist at an inch deep level, do not water. Always allow the soil to completely dry out.
2. Mow every 5 -7 days. Be sure to collect the clippings.
3. Apply a mid-summer nitrogen-rich fertilizer. Nitrogen is known the increase the rate at which Mycelium expires, hence eliminating the possibility for mushrooms to even appear (try to coordinate this application with a thunderstorm, as the lawn must be watered thoroughly right after the application).
4. Add a 1” inch layer of sand, to improve the drainage ability of the soil.

Other Issues we have identified

We learned that mushrooms can be a symptom of certain maintenance habits, which should be modified at least until the mushrooms are no longer a problem.

Thatch

When mowing a tall lawn, it is imperative to gather all grass clippings. Otherwise, they will collect on the grass floor, form a layer that prevents oxygen flow to the roots, and chokes any new grass growth – resulting in bare patches.

We recommend attaching a bag to the mower or raking up the clippings immediately upon mowing.

Mowing Frequency

Keeping the lawn short (1.5” to 2” inch), and mowing it frequently will encourage new grass shoots = maintaining the density of the lawn.

In general, a lawn should be mowed once a week, and not more than a 1/3 of the length of a blade should be cut, to avoid stress to the lawn.

No one likes to see mushrooms on his lawn, but in case you got a few – don’t worry – you will lose them in no time. But now you know how rich and wonderful your soil is, and that your lawn is bound to be lush and green for years to come.

Just water a bit less 🙂