I am new to gardenweb, but have been reading here for a while. Now I have a problem and thought maybe someone here could help. I am growing tomatoes in a greenhouse and some of my tomatoes are forming dark areas near the blossom end, but not at the blossom end. The dark areas are forming in sections around the tomato where the seeds are - in each pocket. They are between the center (equator) of the tomato and the blossom end - never at the blossom end or above the equator of the fruit.

The plants were under fertilized up until about a week ago when I gave them a heavy feeding. They all look healthy and lush now. Also, the weather went from about 10 days of rain to recent sun. I'm thinking the rapid change in growth rate coud have something to do with it? I've added more calcium but don't think it is blossom end rot, so I don't know if this will help. Any ideas? Anyone ever seen this before?

Thank you!

Have you tried searching the forums - this one and the main tomato forum? I just know this has come up before but can't remember what it was.

This is a physiological problem that is usually caused by inconsistent moisture levels (usually overwatering), which interferes with the plant's ability to move calcium. Of course, if there's no calcium in the soil, then you must introduce some with a fertilizer. That's easy to fix. :-)

It's most likely to happen in container grown plants. Some tomato varieties are more prone to BER than others. Lots of people have this problem with plum/roma type tomatoes, especially when they're in containers.

Regular fertilizer, and more importantly, keeping moisture levels consistent will keep the problem to a minimum or eliminate it entirely.