Q. What causes tomato plants to turn brown and die after the first picking? – Becky Downs, Bardstown (Salt River Electric)
A. Hi, Beckie: Tomatoes are susceptible to many insect and disease issues. Some cultivars are more disease resistant than others and just like all other plants, they have a preferred growing environment in which they thrive. A combination of disease resistance, growing conditions and Mother Nature can contribute to the onset of unhealthy plants. There are a few possibilities why the plants turned brown and died.
First, the tomatoes did not get enough moisture and dried out. I know this seems like an obvious answer but the soil can dry out quickly on hot summer days; this is especially true if planted in a container. Other possibilities include, early blight, various wilts/viruses or damage from an herbicide spray. Do you know which tomato you were growing and did the fruit itself have any injury? I assume at this point you’ve pulled your plants but for next season, keep a few things in mind.
Insects and disease can over winter in the soil which is why crop rotation is important. If you have planted tomatoes (peppers, eggplant or potatoes) in the same location for several years you might consider moving them next year. It is always a good idea to buy seeds or plants from a reliable source and plant them in a space where they will receive at least six hours of direct sunlight each day.
The soil should be rich in nutrients and well-drained. The pH should be between 6.2 and 6.8. If you have not had your soil tested you can do this through your County Cooperative Extension Service. Good air circulation is also important in preventing disease. For a complete list of tomato cultivars and their disease resistance and growing vegetables in Kentucky visit: http://www2.ca.uky.edu/agcomm/pubs/id/id133/id133.pdf andhttp://www.ca.uky.edu/agc/pubs/id/id128/id128.pdf