I am growing some herbs and tomatoes in containers this year - no vegetable garden - just patio plants. I am even trying one of the Topsy Turvy containers.
My little tomatoes have brown bottoms. They look like they are rotting, but when I feel the brown part, it is firm, almost leathery. I clipped off some leaves around them, thinking they weren't getting sun and perhaps sitting on a leaf.
Julie in Springfield
Thanks for visiting the blog and emailing. Most likely your tomatoes have blossom-end rot. It appears as a leathery-brown spot on the bottom of a tomato, just as you described. It is more common on certain varieties and usually on staked plants. It isn't really a disease, but a result of poor growing conditions (no direct reflection on your gardening-as I know you have a beautiful yard). Hopefully it does not continue past the first few tomatoes.
It could be from all the rain and temperature changes you have had. The wet weather messes with both the minerals in the soil and pollination. You can help by shaking the plant a little in the mornings--even tap the blossoms to help spread the pollen.
Hint: Avoid high nitrogen fertilizers. Research shows blossom-end rot is avoided when plants can easily absorb calcium. Nitrogen tends to bind the calcium making it hard to absorb. Choose fertilizers high in phosphorus and potassium for healthy tomatoes.
Resources: Iowa State University Extension (picture), The Midwest Fruit and Vegetable Book, Missouri Edition, by James A Fizzell, and eHowto.