Homegrown Notions: Tomatoes - Blight & Blossom End Rot

by Beth Cook, Mammoth Cave Transplants

The vegetable gardening season is well under way and tomatoes are easily one of the most popular plants grown by home gardeners. Growing tomatoes can be a challenge, but being knowledgeable in common diseases of tomatoes can help you be successful. Two of the most common problems, which is a major threat to tomatoes, is blight and blossom end rot. Identifying these problems early and learning how to prevent and treat these will greatly improve your crop.

Blight is a common fungal disease that attacks a plant’s foliage, stems, and even fruit.  Moderate temperatures, frequent rainfall, and heavy morning dew, make favorable conditions for blight to develop. You should routinely scrutinize your garden for symptoms of blight, which include dark lesions on the stems and brown spots on leaves, accompanied by fuzzy white fungal growth during humid weather. To be sure, take a sample to your local extension office for testing. If the growing season is wet, and late blight is present, fungicides will be necessary to protect your plants from infection. We do carry fungicides to help prevent and control an outbreak of blight. Daconil is one fungicide that is commonly used. Tomatoes and potatoes are susceptible to blight at any time during the growing season. 

Another common problem that gardeners encounter when growing tomatoes is blossom end rot. This problem is not caused by a disease organism, but is rather a physiological disorder that results when there is an inadequate supply of calcium available to the developing fruit. Over fertilizing, can sometimes cause problems with the uptake of calcium to the plant. Initial symptoms of blossom end rot generally appear as water-soaked areas on the blossom end of the fruit. Over time the damage becomes a sunken, dark-colored rot. Prior to planting, the main preventative measure is to have a soil test done to determine if adequate calcium is present in the soil. Limestone (a source of calcium) should only be applied if soil test results recommend it. When a need for limestone is indicated, best results are achieved when the limestone is worked into the soil 2 to 3 months prior to planting. Most of us already have planted our gardens, but this can be done this fall to prepare for next year’s garden. Using a fertilizer low in nitrogen can also help in prevention.  Also, be sure you plant your tomatoes in well-drained soil to aid in prevention.

Be sure to keep a close eye on your crop throughout the growing season. Early detection of diseases is crucial to having a successful garden and yummy tomatoes! Happy Gardening from Mammoth Cave Transplants!

~~Gardening is cheaper than therapy and you get tomatoes ~Author Unknown~