Sounds like blossom end rot.

Too much water can be a factor.

Certain tomato varieties are very susceptable, others almost never get it.

In general, it's very common among most paste varieties.

I've found it's at its worst early in the season and tends to resolve as the season progresses.

It's one of the reasons I stopped growing paste tomatoes.

Hey Alamo,

Kdawg is 99.99% likely to be correct. It is true that it is more common in paste type tomatoes, though it can happen in other types.

Someone will come along and tell you to use epsom salts to prevent it, but that is the subject of an ongoing debate. The problem is calcium uptake, not lack of it in the soil and as Kdawg said, it usually occurs on the first gruits of the season. You can do as you did and dispose of them, or some people just cut off the BER part and use the rest. I usually toss them since I have plenty of other tomatoes.

Hope that helps.

Betsy

Here is a link that might be useful: FAQ page on Blossom End Rot

I get blossom end rot almost every year and it does resolve as the season goes on. I've used bone meal when planting (for the calcium) and this year I tried egg shells. I still expect that I'll get it anyway.

Caryl

BER is not a problem of uptake from soils with Ca++, which are most common, Ca++ is taken up just fine by the roots but there's a maldistribution of Ca++ within the plant such that the blossom ends of fruits from some varieties don't get the Ca++ they should/

Tissues taken from plants that have BER fruits show plenty of Ca++ in those tissues, it just doedn't get to where it should get when plants are stressed/

There are many factors that can induce it but the most common ones are too much N or growing in too rich soil and uneven delivery of water. Almost anything that causes stress to plants can induce it.

If soils are known to have no Ca++, which is exceedingly rare, then adding it may help to a certain degree and if soils are acidic that binds Ca++ in the soil and that can be remedied by altering the soil pH.

Carolyn

What constitutes too rich soil, Carolyn?

Caryl

Thanks Carolyn, I did say uptake and should have said distribution. In most cases, having more calcium in the soil will not cure it as it is not an uptake problem.

Sorry about the misinformation.

Betsy

What constitutes too rich soil, Carolyn?

*****

Usually soil that's been amended with too much organic material so that the N content is very high.

So either too rich soil or too much N as added fertilizer cause too rapid growth of plants and that's a stress to the plants and can induce BER.

Carolyn