June 22nd, 2018 by Chris Chapman

Keeping a tidy lawn is always a good idea, even if you’re not a keen gardener. Your lawn can be a play area for your kids, the perfect venue for a garden party, and it can add value to your house. Unfortunately, your lawn is under constant threat from diseases that can kill it off and make it an unappealing, unhygienic place to be. Read on for a list of the most common lawn diseases you’ll encounter in the UK, as well as advice on how to prevent them and cure them!

Red Thread

Red thread is an incredibly common fungus that infects countless lawns every year. It’s so common, in fact, that you could easily be suffering from it every year without noticing! It’s worth inspecting your lawn regularly in order to check for this pesky fungus – but what actually is red thread?

Identifying Red Thread

Red thread is a fungus that attacks lawns from late spring and throughout summer. It causes blotchy, pale patches to appear on your lawn, meaning people often mistake red thread symptoms for drought. You can identify red thread by inspecting these pale patches, where you’ll find short, red needles of stringy fungus (hence the name).

How to Prevent Red Thread

Red thread thrives in mild, damp conditions, so make sure your soil is draining properly when you water your lawn. Try and avoid watering in the evenings, as this is when red thread is most likely to strike. As red thread attacks the grass leaves, not the grass roots, you should also use some iron sulphate to strengthen your lawn and prevent the fungus from killing off your grass. This will mean you can easily mow the fungus out of your lawn once it occurs, before it discolours your grass. In addition, making sure you remove thatch from your lawn regularly will ensure conditions aren’t ideal for red thread to thrive. Thatch is old, dead grass that sits on your lawn. Rake it off or use a scarifier to remove it.

How to Cure Red Thread

The problem with red thread is that often, by the time you’ve noticed it, it’ll be too late! You can treat the area with a fungicide, but your grass will likely still be discoloured with pale pink blotches. The grass will grow back fine as it’s only the leaves that are dead, but with red thread, prevention is definitely the best cure!

Fusarium (Snow Mould)

Fusarium is another extremely common lawn disease, but unlike red thread, it much prefers the cooler, wetter, weather of autumn and winter. It's commonly known as snow mould due to its habit of forming under snow cover, giving you a nasty surprise when the snow thaws!

Identifying Fusarium

Fusarium or snow mould forms circular yellow patterns on your lawn. Each patch will be small, but if there are several banded together they can merge to form a large, yellow, dead patch of grass. While the yellow patches are growing, they may also be covered in slimy white spores called mycelium.

How to Prevent Fusarium

Fusarium likes unhealthy lawns, so making sure your lawn is healthy means you’ll easily be able to fend off this pesky fungus. Make sure the soil is packed with nutrients using fertiliser and iron sulphate, especially if your lawn is young. Fusarium loves wet conditions, so make sure your soil is draining away properly and isn’t covered in thatch, which can encourage damp to form. If you’re maintaining your lawn well, fusarium shouldn’t be a problem.

How to Cure Fusarium

As with red thread, prevention is the most effective cure! However, you can use fungicides to treat fusarium to stop it from getting any worse. Once the fungicide has worked its magic, rake the dead grass and thatch from your lawn thoroughly and sow new seed.

Lawn Rust

Another common lawn disease that can go unnoticed is rust. Rust is usually brought on by drought during summer and can be caused by a range of fungal infections. Lawns infected with rust can produce massive amounts of spores to spread the disease even further, which is not only bad news for other gardeners, it’s bad for allergy sufferers too.

How to Identify Lawn Rust

As the name suggests, rust manifests with orangey-brown, rust-like spots on the blades of your grass. Affected patches of your lawn will also turn yellow as the grass dries and shrivels up. The easiest way to identify lawn rust is to pop a pair of gloves on and run your hands through the area you suspect is infected. If rust is present, your gloves will be covered in rust-coloured spores.

How to Prevent Lawn Rust

As with all lawn diseases, a strong lawn is your best defence. Give your lawn doses of iron sulphate and regularly rake it to keep thatch off your lawn. In addition, go over your lawn with a garden fork and spike it to ease compaction beneath the soil. Feed your lawn seasonally with fertiliser but be wary of using fertilisers that contain a lot of nitrogen (check the label to make sure). This can encourage the fungi that cause lawn rust. Generally, keep your lawn well-maintained; rust thrives on grass that’s stressed or in poor health, so most healthy lawns should fight off rust quite handily.

How to Cure Lawn Rust

In short; you can’t! Fungicide isn’t effective against lawn rust, but don’t fear; rust doesn’t actually kill your lawn. It’ll make it look unsightly and shrivelled for a while, but there isn’t anything stopping your grass from growing back once the rust is gone. Unfortunately, if you’re hit with rust, you’ll just have to wait it out!