It’s important to know the type of soil you have in order to best care for both it and your lawn.
Now if you have clay in the soil there are certain things you will need to watch out for to ensure the health of the soil and the lawn plants. Clay produces unique problems – they are compacted, dense and have poor drainage. They often stay soggy when wet and will dry rock-hard during summer. These problems hinder essential nutrients, oxygen and water from moving through the soil and the result is a root system that is stunted and a lawn that is weak, stressed and more prone to insect infestations, weeds and disease.
Where there is clay in the soil, even if you lay new soil upon it, eventually the clay will build back up through the profile. As this occurs and the roots of the lawn reach the clay base, they will find it difficult to breathe. This will affect your fertilising regime and will often cause thinning of the turf.
Clay soils are traditionally quite acidic and not very receptive to the nutrients available in the soil even after fertilisation. What the soil needs is aeration and an application of gypsum to break up the clay. Undertake a soil pH test and apply dolomite lime in order to raise the pH level to 6.5.
Another option is to use a soil penetrant/surfactant or soil wetting agent – it will temporary create channels and pores in the clay. By increasing the amount of air in the clay, even by a small amount, you can encourage the beneficial soi-building microbes to generate and grow in numbers. Use of a soil penetrant helps to improve drainage, encourage a deeper root system, helps to move organic matter deeper into the soil, and frees up water and nutrients in the root zone.
By creating a more bioactive soil you create a healthier lawn. And an added benefit is that once your clay soil starts to open up, the soil becomes healthier and the earthworms will arrive in greater numbers – they will then work away aerate the soil, digesting thatch and other organic matter and converting it into humus and rich, fertile castings.
Improving the clay soil will improve the lawn. For more help with your soil issues contact the team at Daleys Turf for advice.
Hi I am looking to lay turf on a clay type surface, I have broken all the soil / clay up and gone quite deep with a pitch fork as the ground is soft at the moment. Do you still advise to use gypsum ? What else would you advise to mix with the clay/soil ?
Hi Andrew,
Yes gypsum is a great product to apply, it does take a very long time to take effect. The other thing to do is add plenty of organics, this helps to build better soil structure long term.
Hi how would you recommend fixing clay soil after sir walter has been layed
Hi Michael,
The only way to correct clayish soil is to add gypsum over the top of your lawn along with plenty of organics. This will take years to fix but you should see an improvement in 1 – 2 years. Aeration of using garden fork or machine will accelerate things and is highly recommended. You will need 25kg of Gypsum per 100 square metres applied each year, along with 25 kg of organics, then aerate, then you could top dress using bedding sand hoping that the sand will fall down the holes you have created.
Terry