I think it is two things. First, you have a little catfacing on the bottom of the fruit, which happens sometimes when flowers are pollinated during cool weather. It can be unsightly but it doesn't hurt anything and I just cut off the ugly catfaced parts when slicing up a tomato to eat. Then, because of uneven moisture levels accompanied by other factors, it looks like blossom end rot began to develop, but the fruit mostly overcame it so that you still have a fruit that will be mostly edible when it ripens. You'll have to cut off that bottom spot, but the rest of the fruit should be fine.

Blossom End Rot is common and is all-too-frequently described as a problem that arises from a lack of calcium in the soil, which is a great oversimplification, because you actually can have BER develop in fruit even when your soil has more than enough calcium in it. There are various reasons for that.

BER actually is more of an issue resulting from the way that the plants' vascular system distributes calcium within the plant. All plant cells need a lot of calcium for proper growth and development, particularly while fruiting. Because the plants' primary job is to survive, during times when the available moisture is inadequate, it pulls back the moisture from the parts of the plant farthest away from the root system in order to at least keep the plant alive. When it pulls back that moisture, the calcium goes with it, leaving the fruit temporarily without the calcium needed for proper fruit development and that BER spot begins to develop. Once the plant has adequate moisture again, the vascular system carries the moisture and nutrients, including the calcium, back out to the ends of the branches, including all the fruit. That is why you sometimes see fruit start to get BER, like yours did, but then to recover and survive the BER with just an unsightly scar on the blossom end of the fruit. There is another form of BER that develops internally in the fruit and it is known, not surprisingly, as internal BER. You see it when you cut into a fruit that looks fine on the outside but has a bad black rotted spot inside.

There are other factors in play as well, so you really have to think of BER as arising from multiple causes---not necessarily a lack of calcium in the soil. Often it is a lack of calcium only in the plant, and it also is more common in younger, smaller plants that have a less well-developed root system and vascular system to transport water and nutrients within the plant. BER in general is more common on fruit earlier in the season than later in the season when the plant has a larger and stronger root system.

Another thing about BER that is sort of mind-boggling and is shocking the first time you see it happen is that it is not necessarily a problem only in sporadically dry weather and temporarily too-dry soil. While dry periods are the time when most people see BER and then realize that at some point their plants must have gotten much too dry, it also can happen during exceptionally wet periods. In those cases it occurs when there is too much moisture in the ground and the plant roots literally become so clogged up constantly with water that they cannot take up nutrients (including calcium) in the normal way and, thus, the BER develops.

Avoiding BER is difficult and sometimes impossible no matter how hard a person tries to keep their plants evenly moist. What you should try to do is to keep the soil consistently moist, but never totally dry and never totally waterlogged. In our climate, where we can go from no rainfall for months to 4 or 8 or 12" of rain in a 24-hour period, BER is just going to happen at times. Normally when I see a large BER spot on the end of a fruit, I immediately pull the fruit and toss it on the compost pile. There is no reason to let the tomato stay on the plant if it isn't going to be edible and usable. Sometimes, though, if the BER spot is small and I think the fruit will overcome it and develop it normally, I'll leave that fruit on the plant.

Also, gardeners sometimes can inadvertently cause BER not only with improper watering (i.e. too much or too little) but also by overfeeding their plants. And, there are some types of tomatoes that are more prone to develop it, although there aren't really any that are totally immune to it. (I have only very, very rarely seen it develop on cherry tomatoes though.) Often, paste type tomatoes develop it when they are forming their first round of fruit and the plant needs lots of calcium to support that fruit but the still fairly young plant's vascular system simply cannot transport enough calcium quickly enough and consistently enough to all the fruit.

People often recommend calcium sprays to stop blossom end rot from occurring, but university research has shown (repeatedly) that these do not work and the BER problem self-corrects in time. These products merely get the credit for "fixing" the problem when the fact is that by the time a gardener sees BER on fruit, figures out the problem and goes and buys a calcium spray, the plant already has grown more, the root system is larger, and the more mature vascular system can transport adequate amounts of moisture and nutrients. So, save your money and don't go out and but a calcium spray.

While sometimes, as gardeners, BER does develop because of things we have done (and there are many ways we can contribute to it---underwatering, overwatering, pruning away too much foliage, overfeeding, failing to add organic matter to soil so that it can hold adequate moisture even in times of low rainfall etc.), it often is just more of a natural result of a still somewhat immature plant struggling to get enough calcium distributed throughout the plant.

I have had more BER this year than ever before, largely because we have had significantly below-average rainfall for the first 5 months of the year and below-average rainfall for the last 2 months, and I cannot water enough to make up for that huge rainfall shortage, but I still have had great harvests because the BER was more of a temporary affliction and the plants now are large enough that it just isn't an issue any more. (If I stopped irrigating, it would come back though because even a mature vascular system cannot transport calcium throughout the plant if there is no moisture in the soil.)

Now, you probably know more about Blossom End Rot than you even wanted or needed to know, but I always feel like it is important to stress that it is not merely an issue with a lack of calcium in the soil since it is a more complex issue.

Future fruit likely will be fine as long as your weather is halfway cooperative (and some years the weather is not).

Dawn

To me, that looked like the top of the fruit, and its just like the damage caterpillars do to my tomatoes. The small hole on the left, looks like a worm hole.

And I'm battlin some BER, I let my plants get too dry, and the small new fruit at the top of the plants developed some BER.

Oh, well, I thought it was the bottom of the fruit.. If it is the top, I agree with you, LCDollar.

BER happens.....as we all know. I have been aggravated to find the internal BER in some fruits this summer. I haven't seen that in ages.....maybe not since the summer of 2003, a year that was a lot drier than this one has been. It is frustrating to have a tomato that looks perfect, and then you cut it open and there is the internal BER. At least when you see the BER on the outside, you're expecting the fruit also will be bad inside or, if the BER is really bad on the small fruit, you know it isn't going to outgrow it on its own.

Most of my tomatoes are ugly this year. Stink bugs are the worst problem. Last week striped blister beetles defoliated several plants and now the fruit has sun scald. It is hard to get used to ugly tomatoes but you can cut out the bad parts and have plenty to eat. I usually give lots of tomatoes away but it is hard to find many pretty enough to offer to people.

Thanks. It is the bottom of the plant.

Helen, The last few large fruit I harvested had so much stink bug damage that they looked hideous. I guess I am going to have to break down and spray the plants with kaolin clay next summer.

For whatever reason, I didn't have many blister beetles last year, and haven't seen any this year. At our place, they cycle up and down and I haven't had a really bad blister beetle year in a few years now---so I guess I am overdue.

I'm like you---I hate to give away tomatoes that look much less than perfect. I really should use my brain and yank out 90% of the plants left in the garden. I've really canned all I want to can this year---around 300 pints---and certainly don't need any more tomatoes, and the ones we're getting now are mostly too ugly to give away.

Sorie, You're welcome.

Dawn