My tomatoes are turning brown on the bottom.
Hardiness Zone: 6b
By Cecil from Paducah, KY
June 16, 2010
This is probably blossom end rot. It occurs at the bottom of the tomato and sort of looks like a bruise that may or may not be indented somewhat. Crushed egg shells in the dirt will replace a calcium shortage which is frequently the cause. Also, too much water and/or fertilizer (indicated particularly if you have plants that are very tall but not bearing much fruit) can cause blossom end rot. Pick the affected fruit as soon as you notice the problem so the plant's energy is spent on healthy fruit instead. Usually only affects some of the fruit on a plant, and most often only the first fruits.
Hardiness Zone: 6a
Debi from Niagara Falls, NY
It sounds as though your tomatoes have a classic case of blossom-end rot-a disease commonly caused by a localized calcium deficiency in the tomato fruits. Although it can occur, this deficiency is usually not due to a lack of calcium in the soil. Here is how it often happens:
Calcium in the soil is dissolved by water and taken up by the plant's roots. In conditions of high moisture stress (lots of rain or overwatering), this water is taken up by the plant's vascular tissue very quickly and the water moves more rapidly than usual from the plant's roots to its leaves. A plant loses most of its water through the leaves (transpiration), so naturally after a large uptake of water, most of the calcium is left behind (deposited) in the leaves, before it has the chance to be evenly distributed throughout the entire plant (especially to the fruits, which are the last to receive it anyway). When most of the calcium is deposited in the leaves, it causes a localized deficiency of calcium in the fruit. This eventually causes the cells to collapse, producing the symptoms of blossom-end rot. Blossom-end rot can also occur in plants experiencing rapid leaf growth due to over-fertilization (especially with nitrogen), because the larger leaves increase the amount of surface area available for transpiration to occur, throwing the plant's systems off balance.
To prevent blossom-end rot, here are some things you can do:
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I have had the same problem, especially when I have tomatoes planted in container pots. It is called "Blossom End Rot". I add lime to the soil, work it in and it eliminates the problem. Hope this helps.
LI Roe (08/07/2006)
By LI Roe
I read to dig in egg shells. I did so and began to water longer only twice a week when very dry. It worked. (08/13/2006)
I'm growing tomatoes in a Topsy Turvy planter. The fruit is about 1.5 inches across, and the bottom is discolored (beige). What is the cause, and what can I do to save the other (green) tomatoes?
Hardiness Zone: 9b
By sandralee406 from Beaumont, TX
Blossom end rot is very common in ANY tomatoes. The other people have given you some good treatments. There is a liquid chemical treatment to use before this starts, or you can try some 'home remedies' first. (07/09/2009)
I have a Topsy Turvy tomato planter and my tomatoes are turning dark brown or black on the bottom. I used miracle grow moisture control for the whole plant. Does anyone have clues or ideas for me? My plant is starting to look wilted.
Hardiness Zone: 8b
By Chris from Round Rock, TX
Look up "blossom end rot" and see if the description fits what your tomatoes are going through. It sounds like it to me. If that's it, a simple amending of your soil will cure what ails it. It's more than likely a deficiency of calcium.
Topsy Turvy is a fun way to grow tomatoes, isn't it? Who would ever have thought? We'd plant flowers (something like petunias or nasturtiums) in the top part of our bucket, which often would cascade or drape over the edge. Made it look so pretty. We made our own Topsy Turvy containers using 5 gal wallpaper paste plastic buckets. Worked just great!
Good luck to you.
Julia in Boca Raton, FL (05/11/2010)
I use Yield Booster, 2 TLBS per one gallon of water to make a spray. This stuff helps stop and prevent blossom end rot caused by calcium deficiency. The rainy weather causes the calcium to wash out.
Apply thoroughly weekly and may be combined with other insecticides and fungicides. (05/13/2010)