Usually, the most preferred soil for a lawn is loamy soil. If the lawn soil is mainly sandy or clay, then you can resolve the issue with the addition of organic materials.
If you do not know what sort of soil you have, you can send the sample of the lawn soil to the closest soil-testing laboratory for analysis. The outcome might not be as dependable as the one supplied by the soil-testing laboratory but should be sufficient to ascertain the sort of dirt your yard has. You can get lawn soil analysis from https://biosoilsolutions.com.au/services/soil-biological-analysis-2/ and get the whole info on the soil.
How do these organic substances help the soil?
1. If the soil is clay, the organic matter can help loosen the soil and increase the water drainage capacity of the soil.
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2. If the soil is sandy, the organic substance help improve the water retention in addition to the nutrient-holding potential of your yard.
3. They can help to bring back the earthworms, and other soil-borne insects that enhance the yard soil. But this can only be possible if you know what sort of nutrient is needed. And soil analysis can help you with this.
4. Even the fertilizers help the soil in a better way and support to bring the organic matter into the soil.