Gardener Shoveling in Clay Heavy Soil
amend clay
(Image credit: Lubo Ivanko)

You can have all the best plants, the best tools, and all the Miracle-Gro in the world, but it won't mean a thing if you have clay heavy soil. Read on to learn more.

Steps to Improve Clay Heavy Soil

A great many gardeners are cursed with clay soil, but if your garden has clay soil, this is no reason to give up on gardening or suffer with plants that never reach their full potential. All you need to do is follow a few steps and precautions, and your clay soil will be the dark and crumbly soil of your dreams.

Avoid Compaction

The first precaution you will need to take is to baby your clay soil. Clay soil is particularly susceptible to compaction. Compaction will lead to poor drainage and the dreaded clods that gum up tillers and make working clay soil such a pain. In order to avoid compacting the soil, never work the soil while it is wet. As a matter of fact, until your clay soil is corrected, avoid overworking your soil with excessive tilling. Try to avoid walking on the soil whenever possible.

Add Organic Material

Adding organic material to your clay soil will go a long way towards improving it. While there are a great many organic soil amendments, for improving clay soil, you will want to use compost or materials that compost quickly. Materials that compost quickly include well-rotted manure, leaf mold, and green plants. Because clay soil can become compacted easily, place about 3 to 4 inches (7.5-10 cm.) of the chosen soil amendment on the soil and work it gently down into the soil about 4 to 6 inches (10-15 cm.). In the first season or two after adding organic material to the soil, you will want to take care when watering. The heavy, slower draining soil surrounding your flower or vegetable bed will act like a bowl and water could build up in the bed.

Cover with Organic Material

Cover areas of clay soil with slower composting materials such as bark, sawdust, or ground wood chips. Use these organic materials for mulch, and, as they break down, they will work themselves into the soil below. Working these larger and slower composting materials into the soil itself could cause harm to the plants you plan to grow in that space. You are better off just letting them work in naturally over a long period of time.

Grow a Cover Crop

In colder seasons when your garden is taking a break, plant cover crops. These may include:

The roots will grow into the soil itself and act like a living soil amendment. Later, the whole plant can be worked into the soil to further add organic material.

Additional Tips for Amending Clay Soil

Amending clay soil isn't an easy task, nor is it quick. It may take several years before your garden's soil has overcome its issues with clay, but the end result is well worth the wait. Still, if you don't have the time nor the energy to invest in improving your soil, you can take the raised bed route. By building raised bed on top of the soil and filling them with new, high quality soil, you will have a quick solution to your clay problem. And eventually, the soil in the raised beds will work its way into the ground below. Whatever route you choose, that doesn't mean that you need to let clay soil ruin your gardening experience.

Heather Rhoades
Founder of Gardening Know How

Heather Rhoades founded Gardening Know How in 2007. She holds degrees from Cleveland State University and Northern Kentucky University. She is an avid gardener with a passion for community, and is a recipient of the Master Gardeners of Ohio Lifetime Achievement Award.