The fruit on my containered tomato plants is rippening and most have a big brown/black spot on the bottom.?

Question

The fruit on my containered tomato plants is rippening and most have a big brown/black spot on the bottom.?

Answer 1

Yes, it's blosson-end rot, a common symptom of calcium deficiency that is brought more apparent when there's inconsistend watering.

This happens rather often, even in greenhouses on the first fruits on a tree.  Pluck the tomatoes off and hope the rest of the harvest is better.

Answer 2

You have blossom end rot.  It's common with tomatoes that have had inconsistent watering.  The inconsistent watering causes a calcium deficiency in the plant.

Ways to remedy:  (1)  Water more consistently. (2) Next time you make hard boiled eggs, save a couple of the egg shells and crumble them up and put on the soil.  Boiling the eggs before hand takes salmonella out of the picture.  

Gypsum can replace calcium but before adding gypsum or lime, you should have your soil tested.  The pH of your soil dictates which you would add.

Answer 3

What you have is called "blossom-end rot". Your soil is low in calcium, try adding some gypsum to the soil. Once you have mixed the gypsum into the soil -- water it in thoroughly. Good luck.