Rings on underside of Tomatoes
I have a container garden of tomatoes and all summer long the tomatoes have had this ring around the bottom. We did have an insect problem, but Sevin took care of that. I have to cut off a good 1/4 of the tomatoes when I use them as this is hard and "pithy". I do have a picture I could send if it will help. Thanks for your help.
Certified GKH Gardening Expert
These are called concentric rings on tomatoes and are normally the result of environmental changes that are water related. They are similar to tomato cracking. Here is more information: https://www.gardeningknowhow.com/edible/vegetables/tomato/tomato-cracking.htm