Organic Farmer Network: Network Discussion Summary

Topic: Disease

Ken notes relationship between soil and disease: “I put up a new 30x95 tunnel this winter. A year ago the site was growing trees. Stumps pushed out in September. In the fall I spread a heavy application of aged cow manure, aged chicken manure and lime on the site. My intent was to get the frame up and covered before winter so it would stay warm and the microbial population, in response to the manure dinner, begin to shift from fungal dominated woodland soil, to bacterial dominated soil more suitable to vegetable production. All the rain actually prevented me from getting the house covered til March, and I was concerned that much of the nutrients from the manure had leached out, so when I was finally able to til and plant I also applied feather meal at about 50 # N per acre, sulphate of potash the same, plus a 50 bag of Kelp meal in the house, and 300 # of greensand. I planted tomatoes and cukes. Tomatoes have grown great from the get go. There are 4 varieties of cukes - Jazzer, Tasty Jade, Genuine, and Diva. Many of the Divas died quickly and early on just after that week when it rained and was cold for 5 days. I sent sample's to the NCDA lab and they said there was Pithium and that the soluble salts in the sol were very high (no surprise) and that high salts made plants more susceptible to Pithium. Since then, no more plants have died, the tomatoes and cukes are blooming. I have been drip watering often. The connection between Pithium and high salts made me wonder how many ‘disease’ problems are related to management practices. Backs up that well-known notion that good well balanced organic management results in healthier plants that are less prone to disease.”