You’re heading out to the garden to harvest your beautiful, ripe tomatoes, but when you get there, you find fruit that has dark brown spots on the skin. It is common to jump to the very typical problem with tomatoes, blossom end rot. However, there are two other conditions that are copy-cats in their symptoms: Late blight and buckeye fruit rot both cause similar dark spots on the fruit of tomatoes.

With blossom end rot, the dark spotting will occur on the terminal end of the fruit, where the flower once was. If you see spots on the side or top of the fruit, this is a good indication that the fruit is not affected by blossom end rot.

Late blight and buckeye fruit rot differ in several ways. Late blight tends to have noticeable symptoms on the leaves and stems as well as the fruit. Plants affected by buckeye fruit rot may have plants that appear to be perfectly, but with rotting fruit. The lesions on the fruit with buckeye fruit rot will be firm and smooth with concentric rings, like ripples of lighter shades protruding from the spots. Whereas, the spots on fruit with late blight will be rough and will not have these concentric rings. Ultimately, if you still can’t decide based on the symptoms, consult the recent weather patterns. Late blight thrives in cool, wet conditions, and buckeye fruit rot prefers warm, wet conditions.

If you’re still unsure what is ailing your tomatoes, please give your local N.C. Cooperative Extension office a call and discuss the possibility of submitting a sample to the Plant Disease and Insect Clinic at NC State University.