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The Journal Gazette

Saturday, February 10, 2018 1:00 am

Poor soil in county may hurt garden

Ricky Kemery

Question: My vegetable garden has been a big disappointment. I tilled and added some bagged dirt but the vegetables just don't grow well. What can I do?

Answer: The quality and health of soils in the suburbs in Allen County where you live are generally poor. To build homes, the existing soil is scraped, rolled over and buried to make a new home site. Where once there might have been a healthy forest soil, now there is nothing left but compacted clay subsoil.

Healthy soils produce healthy plants with less chance of disease and insect issues and more nutritious vegetables.

John Ikerd, retired soil scientist from the University of Missouri, reports in his article “Healthy Soil, Healthy Farms, Healthy Food, Healthy People” that one prominent academic study compared nutrient levels in 43 garden crops in 1999 with levels documented in benchmark nutrient studies conducted by USDA in 1950. The scientists found significant declines in median concentrations of six important nutrients in the 1999 crops compared with vegetables grown in 1950.

Another study published in the Journal of Applied Nutrition in 1993 showed that 13 organically grown apples, potatoes, pears, wheat and sweet corn, purchased over a two-year period, averaged 63 percent higher in calcium, 73 percent higher in iron, 118 percent higher in magnesium, 91 percent higher in phosphorus, 125 percent higher in potassium and 60 percent higher in zinc than conventionally grown foods purchased at the same time.

In a 2017 Meta study published in Soil Quality and Plant Nutrition, scientists concluded that integrated nutrient management means improvements in the biological, physical and hydrological properties of soils. This can be accomplished by using combinations of complementary crop, livestock and land husbandry practices, which maximizes additions of organic materials, recycles farm wastes, so as to maintain and enhance soil organic matter, and promote soil micro-organisms. Minimal tillage and crop rotation can maintain and enhance a soil's physical properties by maintaining an open topsoil structure, and breaking any subsoil compacted layer thereby encouraging root development and rainfall inltration.

The addition of organic matter is vital for the health of plants in our area. Canadian sphagnum peat moss and compost are the two most valuable additives for healthy soils. My recipe involves at least two bales of Canadian peat moss, with a bushel basket of compost and a bushel basket of aged manure per 10-by-10-foot area. Add a pound of sulfur to the area if the soil PH is high.

Till this into your soil in the spring and then add rotted leaves or mulch over bare areas. Stay off the growing areas as much as you can.

The Plant Medic, written by Ricky Kemery, appears every other Saturday. Kemery retired as the extension educator for horticulture at the Allen County branch of the Purdue Extension Service.