How to stop lawn dying and growing mushrooms?

Kadoublen

Hi,

I have got this problem with my kikuyu lawn (i don’t really know, that is what the builder told me) for a while now. Most part of my lawn start dying or at least not growing and I found mushrooms start growing around the edge of the little healthy patch. 

I’ve tried liquid fertiliser and no mowing for 4 weeks now, but still not going anywhere better. It is a low traffic area and although We are in a clay soil area with garden soil on top, but the healthy grass grow anywhere regardless. 

What do I need to do to fix it? Thank you very much. 

  

EricL

Hello @Kadoublen 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your lawn.

It looks like your kikuyu lawn is struggling in certain areas while a small patch remains healthy, and the presence of mushrooms suggests there's a deeper issue with soil moisture and organic matter. Since you're on clay soil with a layer of garden soil on top, it's likely that poor drainage and soil compaction are the main culprits. Kikuyu generally thrives in tough conditions, but compacted clay can cause water to sit on the surface, suffocating roots and encouraging fungal growth. The fact that mushrooms are appearing along the edges of the healthy patch indicates there’s excess moisture and possibly decaying organic matter beneath the surface.

Even though you’ve applied liquid fertiliser and avoided mowing, the lawn hasn't improved because liquid fertilisers only provide a short-term nutrient boost and don’t address the root cause. The first thing you should do is aerate the soil thoroughly, especially in the struggling areas. Use a garden fork or a Saxon Lawn Aerator Sandals (available at Bunnings) to punch holes across the lawn to help oxygen, water, and nutrients penetrate to the roots. Follow that with a good-quality soil wetter, like Seasol Super Soil Wetter or Richgro Ezi-Wet, which will help break through the water-repellent layer that often forms on clay soils and allow water to move deeper where the roots can access it.

Next, feed your lawn with a slow-release granular fertiliser such as Scotts Lawn Builder All Purpose. Unlike liquid fertiliser, this will provide a steady supply of nutrients over time and support healthy regrowth. You should also lightly topdress the bare patches using lawn topdressing soil (like Scotts Lawn Builder 25L Organic Lawn Soil Topdress & Underlay or Seasol 25L Lawn Top Dress Mix). This encourages runners to spread and fill in the gaps, but make sure not to bury the existing grass blades—just a thin layer will do.

Water deeply but less frequently, ideally early in the morning, two to three times a week depending on rainfall. This will train the roots to grow deeper and avoid the soggy topsoil that promotes fungal problems. If you suspect grubs or root rot in the dead areas, gently lift the turf to inspect the roots. If you find white curl grubs, treat the area with Yates Grub Kill & Protect. For fungal issues, consider Yates 150g Mancozeb Plus Garden Fungicide And Miticide to help manage any underlying infection.

Autumn is actually a great time to repair your lawn because it’s still warm enough for kikuyu to grow but not so hot that it stresses the new growth. Once the lawn starts recovering, resume regular mowing but don’t scalp it—leave it around 4–5cm tall to keep it strong. Over time, adding gypsum to your soil can help improve clay structure more permanently by breaking down compacted particles and improving drainage.

Please remember to wear personal protection such as gloves, goggles and a mask when using chemicals in your garden work.

If you need further assistance, please let us know.

Eric