Yield, Vitamin and Mineral Content of Four Vegetables Grown with Either Composted Manure or Conventional Fertilizer

Although there is a considerable amount of interest in organically produced crops, there is a lack of scientific research evaluating vegetable production from paired organic and conventional experimental plots. A comparative study was conducted for three years in a Pugwash sandy loam near Truro, N.S. Five replicates of two treatments (organic and conventional) were established annually for carrots, cabbages, potatoes and sweet corn. The addition of pesticides, lime and NPK fertilizer to the conventional plots followed the Nova Scotia Soil Test Recommendations; while lime, rotenone or Bt and composted manure were applied to the organic plots according to the guidelines established by the Organic Crop Improvement Association, Inc. (OCIA). The compost was made using chicken or beef manure and straw. Compost was analysed for total N and applied at rates appropriate to each crop assuming 50% N availability during the cropping season. Marketable yields were recorded and representative leaf samples and ...