photo courtesy of Flickr and chidorian
It’s a common question: What to add to clay soil to grow vegetables. Anyone who has tried to create a lush, fertile garden from clay soil knows this is no easy feat. Clay soil clumps together, making it difficult for new plants to establish a root system and when it gets wet it offers little to no drainage, leaving your plant’s roots sitting in soggy soil. Who needs that? Certainly not your vegetables.
How to Loosen Clay Soil
The first step to improving your soil is to break up all the big clumps in it. Use a rototiller and, set to dig at least a foot deep into the soil, make several passes over your garden’s soil, until it is clump-free and loose.
Next your going to need to add something to lighten up this heavy soil type. Washed, chemical-free sand is a perfect choice, as is compost or top soil. Sand will give you the drainage capabilities clay soil so desperately lacks, so, if it’s available, make this your first choice. Spread it liberally over your clay soil and use the rototiller once again to mix the sand, or other suitable material, into the clay soil.
Fertilizing Your Clay Soil
Fertilizer should always be added to clay soil, as it lacks the natural nutrients needed for your vegetables to thrive. Always test your soil to determine its pH level before adding anything. Once you have your soil’s pH number you’ll know exactly what it needs.
Add lime to soil if the pH number is acidic, meaning its pH level is below 5.8. If your soil is alkaline, with a pH above 7.2, iron sulfate should do the trick. Of course, some vegetables require a little more or less, but this will start you off on the right foot and you can adjust as needed per your different vegetables specific needs.
A word of caution: once you have tilled your clay soil and added the sand (or other material) and fertilizer avoid walking in areas you plan to plant in. Clay soil still has a tendency to compact easily, so either stay out or make a designated walkway through the middle of your garden for foot traffic.
Don’t want to tackle that awful, clay soil? Have a look at our article on creating raised vegetable gardens, and avoid that clay soil altogether.
Join us next time when we’ll talk about how to grow vegetables in containers. Learn why this type of gardening is becoming so popular!
Until then—go plant something tasty!
