Changing a clay soil is not an overnight process but with the right advice and a little bit of patience, you can have a healthy soil that is rich and easy to manage.Clay soil has the smallest particle size of any soil, only visible under an electron microscope. There are a lot of particles in a small space, meaning not a lot of space for air or water to move through.

This creates a soil that is very dense and hard for plant roots to grow through as well. The good thing about clay soils is that they have the highest ability to hold nutrients and they can be turned into a friable soil that is great for growing in.

Initial steps

  • The first step is to add Gypsum to the soil at the rate of 1-3 kilos per metre,digging this into the top 10-15cm well. Clay Breaker 25kg
  • Gypsum works by breaking the clay into small crumbly pieces which are easier to work with. It is a natural product that can be added to organic gardens and is pH neutral.
  • The next step is to add organic matter in the form of compost to your soil.Add 5-6 cm layer of compost on top of the soil, and work in to about 10 -15cm.
  • When mixing compost into your soil the best way to think about it is like mixing a cake. The more you break up the lumps and mix the ingredients,the better the results.
  • Leave the soil to settle for several weeks so that the compost and gypsum work away at changing your soil structure.

Long Term Management

Clay soils demand a short-term and long-range strategy to build and maintain a rich fertile soil. The initial strategy is to break up the clay and add organic matter to the soil. Because clay soils do not generally promote a lot of biological activity,it is important to get that activity going.

Large amounts of compost properly mixed in will rapidly breakdown, leaving some slower long-term parts of the compost behind. By adding regular compost or organic material to your garden, you increase the long-term organic content in the soil. This increase of long-term organic content is important for adding nutrients and building soil that is healthy and usable from clay soil.


Helpful Hints

  • Grow a cover crop in your garden if not planting over winter. This adds valuable nutrients as well as adding to the structure of your soil. See our Cover Crops How to guide.
  • Clay soils can dry out and shrink and swell when wet. Make sure that the water content is not too low or high when working it.
  • Resist the urge to use sand to add to your clay soil. It can become compacted and almost concrete like.

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