Red Thread
Red thread occurs in humid conditions or after heavy dew, usually from May onwards and is the most common lawn disease. They show as pink or red patches, and the fungus causes the leaf of the grass to die. Removing clippings after mowing, feeding your lawn, aerating and scarifying will all prevent recurrence.
Fairy Ring
Fairy Ring will appear as a ring of dying or dead grass, with a border of dark, healthy grass. The name 'Fairy Ring' comes from the fact that there is quite often moss and toadstools present. There will also be fungal growth within the soil. The lawn will become water repellent where the fungus is growing, which is why the grass will start to die.
There are a few things you can do to control Fairy Ring. The first is to spike around the area using a garden fork, then apply a wetting agent. This will help break down the water repellent nature of the soil. If after 5 days, the soil hasn't had a good amount of rain it's important to provide water using a sprinkler or hose.
Fungicides can be used to kill the fungal growth within the soil, the best time to apply is during spring, as the Fungus is most active.
Algae
Algae will appear as dark green or black jelly on a lawn, and usually occurs in damp, cool weather. It usually appears on grass beneath trees or on over mowed grass. Underlying conditions such as poor drainage and non-aerated soils are usually the cause of algae on lawns, so correcting these will reduce the chances of recurring algae.
Fusarium & Snow Mould
Fusarium often occurs in autumn and spring in cool, wet conditions. It presents itself in yellow, straw-like patches. This can also occur when grass has been covered for long periods by snow, giving it the name 'Snow Mould'. This disease is damaging because it can kill grass plants.
Lawns with a heavy thatch layer, compaction, poor drainage and shade are more prone to Fusarium, so if an outbreak is present, it probably means that your lawn conditions are not the healthiest. Putting a little effort into looking after your lawn can go a long way, and should help prevent Fusarium. Try and avoid compaction, and make sure there are no problems with drainage in your lawn.
Rusts
Lawn rust generally appears as patches of yellow grass, and spores will be present on the grass leaves. Rust does not usually kill the grass, however may damage it severely. Maintaining vigour by feeding your lawn when necessary will help prevent rust. If you already have rust present in your lawn, mow and remove the clippings. This should lower the amount of rust present on the leaves.
Looking after your lawn
A lawn is relatively easy to look after as grass plants are tough. However, there are things you can do to make sure you keep your lawn healthy and green.
Feeding
Using a pre-seeding fertiliser can make a massive difference when seeding a new lawn. For best results, rake in 3-5 days before sowing. Feeding the lawn will increase vigour and help prevent weeds and moss from establishing. A granular blend fertiliser should be applied between March and September. There are many different types of fertiliser including slow release lawn feeds, which only need applying once a year, or liquid fertilisers that would need 3 or more feeds per annum.
Spiking
Spiking is important for drainage and compaction, and ideally would be done once a year (Around October would be best). Spiking has many benefits including:
- Reducing thatch
- Increases air to the grass
- Improves soil drainage
- Stimulates growth of new roots
- Makes the lawn more resilient to drought in the summer
Spiking can be done with an ordinary garden fork, making holes to a depth of between 1 and 6 inches. It can also be done using a hollow tined machine, aerating shoes or with a solid spoke machine.
Rolling
A light roller, half-filled water roller or a pedestrian lawn mower roller can be used to firm the surface of your lawn. You can do more harm than good with a roller that is too heavy so caution should be taken. Some mowers have a roller on, and if so, this is plenty for firming the surface of your lawn.
Mowing your lawn
When the lawn is first sown: Make the first cut when the grass reaches 5-8cm. Cutting the grass regularly:
- Stimulates shoot growth
- Increases establishment
- Improves the look of the lawn
- It is important to cut the grass down to the desired height gradually and not take off too much at one time. Too heavy a cut will be harmful to the grass.
Once the lawn is established: Start cutting in March, and end in October, ideally once a week depending on your preference of appearance. During the summer months where the grass growth is accelerated, it may need cutting more than once a week. A light cut may be also needed over the winter to keep a neat appearance.
