Holmes,

Blossom end rot is a disorder caused by a shortage of calcium to the developing tissue in the walls of the green tomato. Since the blossom end is at the terminus of the fruit, the most severe shortage occurs at that point.

Whatever causes the shortage of calcium available to the developing fruit occurs at the roots of the plant where the calcium, and the vast majority of other nutrients required by the plant, is drawn up from the soil.

The causes are various but usually are associated extremely dry weather desiccating the soil and locking up the available calcium. But there can be other reasons like sopping wet soil drowning the root system. Another cause could be excessive root pruning like if roto-tilling or too deep chopping with a hoe severs a lot of the fine feeding roots that spread out in search of nutrients.

Have you experienced any of these climatic or cultural problems this year? If so, one or more of them may have lead to your BER.

Some varieties of tomatoes are more susceptible to BER than other varieties. Roma happens to be one of the susceptible varieties.

Most soils have sufficient calcium for tomatoes ... at least that's the case in most all Indiana soils and generally throughout the Midwest. Where do you grow tomatoes? If you suspect your soil may be low in calcium, you should have it tested and add if necessary, but I suspect it may be one of the other environmental factors like drought, chronic wetness ... or just irregular irrigation, where the plant all of a sudden has it's calcium supply interrupted at a critical stage in the development of the green fruit.

Thanks for the reply. I had the tomatoes in pots this year. 10 huge pots. All did well, except for the Roma with the end rots. And yes, the weather was extremely hot and humid this past summer. I thought it may have been me excessively watering. I cut back and it was the same. Now that I know Roma is one of the susceptible varieties, I can better handle it next year. Is there another plum variety that would do well or maybe better than Roma? I did grow an Heirloom Black Plum and that this wonderfully well, with maybe a handful of blossom end rot. The Roma that were harvested were exceptionally sweet, so I may just stick it out and try to perfect the growing process of this variety. Thanks for the reply.

Holmes,

I'm gonna let someone else like Korney talk about growing paste tomatoes in containers. He'll be able to give you a tremendous amount of good info on avoiding BER in containers.

The only paste tomatoes I've grown in containers was Health Kick in 2005, and an unnamed dwarf heart shaped one I grew this year. Neither had BER, while at the same time I did have BER on Silvery Fir Tree and Lime Green Salad in containers ... I'm not a container expert.

Two paste tomatoes I've grown in the past two years that had zero BER (while a few other tomatoes in the same raised bed did have BER due to drought) were Opalka and Romeo. Both are the kind of paste tomatoes that have pointed blossom ends ... so I don't know if that helps resist BER.

Let's let some other folks chime in here.

this year, I had most of my tomatoes planted in raised beds with lots of compost and mulch.............they all did just fine avoiding BER.
The other 50% of my tomato plants were along my chain link fence, in the ground without compost or mulch. All of these got BER. And some were the same variety as I had in the raised beds that did not get BER. Moral of story: Plant with lots of compost and mulch.
All plants were watered about the same.

I had the same problem and did a little more research. I had heard the low calcium and inconsistent watering ideas, but making the necessary adjustments didn't help. I dumped pleny of calcium into each bed, kept everything watered. Still got BER.
Upon further research, I found a site also mentioning that cold roots can be the culprit, and I have a feeling that's what is doing it for me. I may be planting when the gound is too cool.
Next season I'm increasing the spacing between plants, letting more sun in, and I'll plant when the ground is warmer.
Has anyone else noticed more BER on plants that are in the middle of the row vs on the end of the row where there is more sun?

Personally, I don't think the cool ground is gonna help you, but you might try it on a few plants.

Am gonna stick to compost, manure, and lots of mulching again next year. Worked fantastically for me this summer, so why change success. lol

The mulch keeps the roots cooler if anything.

I plan on trying several new (to me) heirloom varieties of tomatoes next year.....large but good tasting ones. I hope the weaher cooperates next year. Was hot and dry this summer......ran my water bill up keeping them watered.

anyone have Neves Azorean Red seeds to spare?