The Bottom of My Tomatoes are Turning Brown

Question:

I was wondering if anyone knew why tomatoes ripen, but on the bottom of the tomato they turn brown and rotten. Any help would be great. Have a Blessed day.

Hardiness Zone: 6a

Debi from Niagara Falls, NY

Answer:

Debi,

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:

1. Keep the proper soil pH. This will enable your plant's vascular system to take up nutrients properly. (Tomatoes need a pH of 6.5 to 6.7)
   

2. Don't over-fertilize. Many gardeners use fertilizer as a substitute for good soil. This is a mistake that will not support good plant growth in the long run. Get a soil test and amend your soil as necessary with organic nutrients. A soil test will also shed light on whether or not your soil is deficient in calcium.
   

3. Water evenly and consistently and mulch around your plants to conserve moisture. This will help prevent your soil from drying out and keep you plants from experiencing the stress brought on by sudden changes in moisture.

About The Author: Ellen Brown is our Green Living and Gardening Expert. Ellen Brown is an environmental writer and photographer.

Answers:

The Bottom of My Tomatoes are Turning Brown

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 Roseanna

The Bottom of My Tomatoes are Turning Brown

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)

By Lynda