As Bill said, some varieties are bred to have thicker skins - for shipping protection is my guess. However, it seems that hotter temps and very dry air or inconsistent moisture levels in the soil can also contribute to the problem regardless of the variety. It's part of the plant's natural defense mechanisms. I have found it to be a sometime problem on Rutgers and Celebrity in the past. Later fruit, assuming the weather co-operates, should be better but since plants in containers are prone to developing more problems than those in the ground, it stands to reason that they would be more easily and quickly affected. Mulching the plant helps and so does doing whatever you can to maintain a consistent moisture level. Good luck. ;) Dave

It's directly related to the variety you grow. I don't know if growing conditions have any influence. But a thinner-skinned tomato is more likely to split. I have been growing Romas for the past few years because they seem to be a happy medium between skin thickness and splitting. This year I also planted Heartlands and (I think...) Manitobas (I lost the tag) but they haven't ripened yet so I don't know what the skins are like.

Also, some tomato varieties are bred to have tough skins...less fragile for shipping, used for canned tomato products etc. Picking tomatoes too early and then allowing them to "ripen on the window sill" will often result in tough skins. Skin gets thinner at the end of the ripening (on the vine) process. They also have better/sweeter taste if allowed to fully mature on the plant.

All varieties of my cherry tomatoes this year seem to have very tough skins. What causes this? Is there anything I can do about it? **** From all the folks who have asked about that and received answers the consensus seems to be it's the particular weather in a certain growing season. No, no specific aspect of the weather to note since different folks have different answers. So no, you can't do anything about it as far as I can see. There are some varieties that have tough skins whenever they're grown and in my experience one of them is Roi Humbert, aka King Humbert. Carolyn