Whether you’re an avid gardener who has recently moved to a property with clay soil, or you’ve been there a while and think it’s finally time to remedy the issue, you may be interested in learning how to improve clay soil.

In today’s article, we explore some tips for testing and subsequently improving clay soil, along with some examples of plants and trees that will thrive in clay soil conditions.

Give it a test

Testing your clay soil can help you to figure out how to remedy it. There are a few different tests you can undertake at home to work out what’s going on with your soil and what it may need. 

One test is an aggregate stability test. To conduct this test, grab a jar and fill it with clear water. Take a few crumbs of dry clay soil and place them into the water. Next, sit back and watch what happens. If you notice a milky cloud appearing around the soil then this tends to indicate clay soil is present. 

Add gypsum

Another test is checking to see if gypsum could improve your soil’s quality. Gypsum is a mineral often used as a fertiliser. To do the gypsum requirement test, simply place some of the soil in a jar of clear water and shake it about until it produces a milk-like consistency. Place the jar to stand for around 10 minutes and then check to see the results. If the dirt doesn’t settle and leave the water clear, it should respond well to added gypsum. Add some gypsum to this test soil and see what happens – if it clumps together that’s a good sign that the gypsum should work. Conversely, if it falls apart, you should try adding compost or other organic matter. 

When you’ve tested your soil and worked out that gypsum should help improve the quality of your clay soil, you can move on to adding it to a larger portion of dirt. To do this, you’ll of course need to know how much gypsum to add. As a general rule, begin by adding around 200g of gypsum per square metre of clay soil. Place this in the soil, let it sit for a while, and then take a new sample to add to a jar of water. If there’s enough gypsum added, the soil should settle and leave the water clear within 10 minutes. If not, try adding a little more gypsum and then redo the test. 

Add organic matter

Another remedy for clay soil is to add in organic matter. Mixing organic matter into your clay soil can help create a more fertile soil and prevent compacting. Organic matter can consist of aged manure, leaf matter, or compost. If you make your own compost consisting of kitchen and garden scraps, this can be an ideal addition to clay soil. Compost for clay soil can be your regular homemade garden compost. This means it can include a mix of grass clippings, coffee grounds, and veggie scraps. Manure can also be mixed into clay soil, as can leaf matter. Organic matter works by improving the drainage of your clay soil, while also providing additional nutrients and assisting with aeration. There’s no exact amount of organic matter to add in – just start by adding in a few centimetres of matter to dry clay soil and spreading it through evenly.

What is clay soil good for?

If all of this seems a little too much effort and you’d rather leave the clay soil as it is, you can simply incorporate plants that thrive in this type of environment. Creating a garden of plants that thrive in clay soil can be a simple solution for those who don’t want to add any fertiliser or organic matter to their soil. Some plants that grow well in clay soil include:

• Old Man Banksia
• Red Stemmed Wattle
• Tall Sedge
• Long-leaf Wax Flower
• Petunia
• Willow Peppermint
• Knobby Club-rush

Finding out you have clay soil in your garden doesn’t have to mean the end of your garden plans. Add gypsum or organic matter to clay soil to remedy the issue, or simply get around it by choosing plants and trees that grow well within this type of soil.If you need any advice on how to manage garden care with clay soil and you’d like a professional to take a look, don’t hesitate to contact your local Jim’s Mowing representative today!