Test for Clay or Sandy Soil
Firstly, to determine an optimum lawn fertiliser programme we need to establish soil type.
This is because different soils hold and release water, air and nutrients at very different rates. This is going to have an effect on the demands of the grass and on the assimilation of nutrients. It’s not critical to get this right, just beneficial. You’re paying for the fertiliser so you may as well get the best bang for your buck!
Clay and dark soils are richer in nutrients and retain them readily so requires slightly lower levels of nutrients. For example our fertilisers for clay soil in spring don't contain phosphate as this is rarely in short supply in these soils. Sandy soils on the other hand drain more easily so requires a slightly higher dose to get the same result.
Have you got clay or sandy soil?
If you don’t know take a small sample of soil from your garden. If you think the soil in your lawn is different from the rest of the garden then use a bulb planter or spade to lift a small area of lawn turf and take a golf ball size bit of soil from 2” to 4″ down.
The soil needs to have some moisture in it for these tests so do these tests after some rain.
Squeeze the soil in the palm of your hand; if it forms a sausage shape and stays together when you open your hand its clay based soil. If it crumbles into a few or more pieces then a sandy base is more likely.
Take a pea sized bit of soil and smear it between your fingers. If it feels reasonably smooth or even silky it has a clay base. If it feels finely ‘gritty’ then it has a sand base.
Hopefully the results from your two tests give the same answer!
You can take this a step further by getting a soil analysis done. If you are going the whole hog and intend investing a lot of time and money in your lawn then a test would be a good investment.