How to deal with waterlogged mouldy soil?

[MattB]

Hey folks - following all the rains in SEQ over this year, parts of my lawn have been left in a very sorry state. The lawn itself was waterlogged for an extended period, and then on top of that we then had an infestation of lawn grub (I'm guessing they like wet conditions!). The grass has died off in large patches, weeds have cropped up and a new one for me: we have mould on the soil.

I've tried a few things so far in terms of aerating the soil, and also dealing with the lawn grub using Scott's pest control... and that seems to have dealt with that particular issue. I am dealing with the weeds with a selective herbicide. But, having never dealt with mould/moss like this before... any suggestions on how to tackle it? I'm attaching a picture to give a better idea of what I'm dealing with. 

Also not sure whether I should be going to gypsum route to help deal with the compacted muddy soil too?

Thanks in advance!

[Jason]

This is a good question that I'm sure many others in NSW and Queensland are struggling with @MattB.

Let me tag fellow Queenslander and lawn care expert @Adam_W to see if he can kick off the discussion for you before @EricL is back on the site this afternoon. Adam has written these helpful guides that you should find useful - How to fix a muddy lawn and How to install garden drainage.

You might also like to share with us whether you've had previous issues with drainage ever before this year and what drainage do you currently have? Have you ever considered adding extra drainage like fellow Workshop member @Ben in this project - Drainage to fix a muddy lawn?

Welcome to the Bunnings Workshop community. We're looking forward to reading more about your project and plans for around the house and garden.

Jason

[MattB]

Thanks @Jason - much appreciated! We've only actually been at this property for two years now so don't have too much history to fall back on, but the previous year there were no issues with drainage like there have been this year. Going by this event though, definitely think I will need to explore the garden drainage installation article you linked to. Thanks  

[EricL]

Hello @MattB

Allow me to welcome you as well to the Bunnings Workshop community. It's a pleasure having you join us, and thanks for sharing your question about water-logged mouldy soil.

It's great that you've received excellent advice from my colleague. Proper water drainage is the key to preventing parts of your garden from getting waterlogged. However, getting mould infestation in the soil is another problem altogether. Looking at your photo, the green algae your looking at is quite common and is caused by excess water, light exposure, poor air circulation, and humidity. 

Although it will not harm any plants you have nearby it is an indication that the area around your plants is susceptible to disease, such as root rot. It also becomes a breeding ground for other fungal infections. Before you start digging, I suggest drawing a plan with pen and paper to see where are the best places to put the drain hoses in. Once you've planned that out you can now calculate the amount of drain hose you'll need and where you'll need to connect to in your current drainage set-up.

I suggest using a Slotted Socked Draincoil, this will prevent sandy soil from settling in the drain pipe and clogging it up. When the excess water has been diverted away the soil in the surrounding area should normalize. Your goal is to remove all the excess moisture in the soil to prevent the algae from reproducing.

Please keep us updated with your progress, we look forward to seeing your water-logged soil repaired.

Eric