Few things drive a person crazier than a fairy ring making its mark in the middle of a beautiful green lawn. You’ll know you have one when a lush green ring appears and is followed by a dead brown ring. Sometimes just a brown ring appears. Both rings birth mushrooms and the mushrooms come & go. Fairy rings can be stubborn and difficult to eradicate. Let’s take a look at how fairy rings work and at some strategies to deal with them.
What causes fairy rings?
- Fairy rings are caused by fungi – fungi feed on dead & composting material in the thatch layer of the lawn.
- Some varieties emit nitrogen – at first the lawn looks healthier and that’s what causes the dark green ring.
- Some varieties are hydrophobic – they hate water so then they create a very dense mat of mycelium fibres – causing the grass to turn brown from being starved of water.
- Other varieties may deplete the soil nutrients and others produce toxic levels of hydrogen cyanide – with the same net effect as the hydrophobes, causing the grass to die.
How does one get rid of fairy rings?
- Eliminating fairy rings can be a challenging task but if you keep at it and are diligent, the odds improve at ridding yourself of them.
- Fungicides are generally ineffective, producing inconsistent results at best because the mycelium fibers stay in the lawn; so save your money.
- Listed below are some strategies for fairy rings:
- Remove anything that may decay in your lawn before you put it your lawn in.
- Level with clean, fresh top soil before you lay out your sod or sow grass seed.
- Keep your lawn healthy with regular mowing and fertilizing.
- Dethatch and aerate your lawn regularly, about every 2 years.
- Fertilizer can mask the symptoms of the fairy ring.
- Do a deep root fertilizer to get under the mycelium fibres, described in more detail below.
- Wondering what the best fertilizer for your lawn is? Check out this link to our blog on fertilizer Unwinding The Fertilizer Numbers
- Get through the Thick Tangled Fibers
- Aerate dead & dying rings by poking holes in the ring with a garden fork or crow bar. It is recommended that you get anywhere from 10” deep to 24” deep. Aerate to 6” on either side of the ring.
- The rationale for this technique is to get through the thick mycelium mat and kill the fungi by watering the area heavily. This type of fungi doesn’t like wet soil, they’re hydrophobic, so they will die in wet conditions.
- Water the ring every 2 days or every day for at least a month – if you can add a little bit of a mild dish soap to the water to reduce the surface tension of the water, do it. Surfactants like soap will make the water more absorbable.
- Fertilize deeply with a water soluble fertilizer every 4-6 weeks.
- Rake or pick mushrooms as they appear.
- Complete Removal of the Ring
- This is the go-to when all else has failed – take out the infected turf and 1 -1.5 feet around either side of the ring.
- Roto-till, reseed or put in new sod.
– by Sharon Wallish Murphy