It's officially tomato season at our house, and, oh, how sweet it is! While it hasn't damaged too many fruits, I have noticed my first case of blossom-end rot since I've started gardening. It's pretty easy to diagnose blossom-end rot. Basically, you're dealing with blossom-end rot if the blossom end of your fruit shows signs of, um, rot. It's quite an appropriate name, it seems.
This tomato (picked from a neighbor's garden) looks great from the top.
But, turn it over, and you'll discover that brown, leathery patch of rotted tomato flesh.
I've talked to several local gardeners who are currently experiencing this problem. It's no surprise, either, since the primary cause of blossom-end rot is insufficient moisture, and we've been how many days/weeks without rain now?
Anyway, for those gardeners who aren't familiar with this condition and are shocked and dismayed by that hideous leathery patch, I've got only good news for you.
It's not a disease; it's a curable disorder. In other words, there's no need to pull your plant up by the roots and go tomato-less until next year.
The rot is caused by a lack of calcium reaching the fruit. Usually, in organic gardens, this has nothing whatsoever to do with the calcium content of the soil itself, and everything to do with the plants not having enough of the calcium-delivery-system -- water. Besides a lack of moisture, over-fertilization is another frequent cause of blossom-end rot. According to Rodale's Vegetable Garden Problem Solver, "Applying too much nitrogen fertilizer may cause blossom-end rot by stimulating so much leaf growth that there's too much competition for calcium." Since my plants are not super bushy, I suspected that my problem stemmed from the drought, but it did seem like the perfect time to try out one of my Mother's Day gifts, a pH soil tester.
According to my tester, our soil pH is just fine at 6.5. If it measured much lower, it would benefit from the addition of lime.
If you have some affected fruits currently green on the vine, pluck them off and feed them to the chickens or compost pile. There's no need to keep them there when new, healthier fruits could make better use of the plant's resources. If, however, you happen to bring in a ripe tomato that has been affected, just slice off the yucky portion, and use the rest. While it's not a pretty fruit, worthy of the farmer's market, it should still taste just fine.