Clay soil is great if you want to make bricks. But if you have visions of flower beds and vegetables growing outside your windows, this soil type can make you wonder if those dreams can come true. Improving the condition of clay soil is possible, it just takes a rototiller and some patience. Depending on how compacted your soil is, you could enjoy the fruit of your labor in just a couple of growing seasons.
Test the Soil Moisture
Rototilling soggy clay soil produces beds filled with clumps, which is not conducive to sowing seeds. Allow waterlogged soil to dry out before tilling. Test soil moisture by scooping up a handful of dirt and rolling it into a ball with your hands. If it sticks together, it’s too wet. Wait a couple of days, then retest the soil moisture. When the balls falls apart easily from squeezing, the ground is ready to till. Conversely, when clay soil hasn’t been worked for a while it can become highly compact and tough to till, even when dry. To make things easier, water the area to be worked with a garden hose and let it dry out for a day or two before tilling.
Till Shallow, Make Several Passes
Whether you’re breaking up ground to make a new garden bed or tilling the vegetable garden after a long winter’s rest, work clay soil a little at a time. Making several passes at shallow depths prevents dirt clods and the tiller from jumping out of control from overworking it. Start by setting the tiller at its shallowest setting and making one pass over the garden bed. For the second pass, add 2 inches to the depth and till in the direction perpendicular to the first pass. Continue to add 2 inches depth and change direction each successive pass until you reach the desired depth.
Amend for Drainage
Improve drainage and aeration in your clay soil by adding coarse organic matter. Use finished compost, partially rotted leaves, or pine needles, to name a few. Spread a layer of organic matter 3 to 4 inches deep on top of your tilled bed, then rototill it in to a depth of 7 or 8 inches. Do this annually and you should see improvement in the soil’s structure. If you don’t see improvement as quickly as you’d like, add a layer of coarse sand 1 to 2 inches deep and till it in with the organic matter. Adding sand without the organic matter can form concrete-like soil, so avoid this.
Maintain Going Forward
Adding amendments to clay soil makes it easier to rototill over time, but keeping it in the condition you desire requires ongoing maintenance. Tilling in soil amendments in the fall allows soil microbes to work over the winter to improve soil structure, and the soil to dry out quicker in the spring. Rototilling the soil again in the spring prepares it for planting and incorporates the decomposed amendments more thoroughly into the soil, resulting in better aeration and drainage throughout the summer watering season. Rototilling between rows during summer months keeps the soil aerated throughout the growing season.
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