How to Build a Garden on Clay Soil

Incorporating manure into clay is an inexpensive way of aerating clay.

Hard when dry and sticky if wet, in high concentration in your garden soil, clay creates a watertight-growing medium unfriendly to many plants. While lilac and butterfly shrubs don't mind the heavy soil, vegetables and many flowers do. If you don't plan to grow plants adapted to clay, incorporate organic matter into your garden bed. The soil will remains clay but with better water and air circulation underground.

Things You'll Need

• Mechanical tiller
• Compost
• 1 lb. 13-13-13 fertilizer per sq. ft.
• Rake
• Soaker hose
• Organic mulch

Instructions

1. Till the soil 9 inches deep. Incorporate 3 inches of organic matter; such as compost, manure or dead leaves; into the ground.

2. Add fertilizers to the clay soil the crop needs. Submit a soil sample to your county cooperative extension office for nutrient and pH analysis. The results tell you exactly how to amend your soil based on its current composition. Without a soil test, incorporate 1 lb. of a 13-13-13 fertilizer per 100 square feet 4 inches into the soil.

3. Rake the surface to a smooth planting bed after incorporating the organic matter and the fertilizer.

4. Space the planting holes in your garden bed according to your crop's requirement. Plant beet seeds, for instance, 2 to 4 inches apart in rows 1 foot from each other. Dig the holes based on each plant's needs. If you have beet seeds, sow them ½ to 1 inch into the soil. Nursery staff and your local cooperative extension service have spacing and depth information for a wide array of plants. The back of seed packets also offers planting instructions.

5. Plant your crop and install a soaker hose 2 inches from it for irrigation. This method keeps the foliage dry and reduces the incidence of disease. It also uses water efficiently by delivering it straight into the ground instead of throwing it up in the air, where some of it evaporates or lands elsewhere. Give most plants 1 inch of water a week, but follow the specific irrigation requirements of the plants in your garden.

6. Apply a 2-inch layer of mulch, such as shredded bark or wood chips, around the base of your plants to suppress weeds, insulate the roots from extreme temperatures and to reduce water evaporation. The decomposing organic matter also helps to maintain the clay soil well aerated. Refill the mulch layer as it breaks down.

7. Harvest edible and ornamental crops just as the fruit or flowers reach maturity, as they decay quickly if left on the plant.

References

• North Carolina State University: Growing Tomatoes for Home Use; Larry Bass; March 1999
• University of Illinois Extension: Step 5 - Prepare and Care for the Soil Properly
• University of Illinois Extension: Step 2 - Plan Your Garden Layout
• University of Illinois Extension: Step 7 - Keep Down Weeds