Tomato Woes and Fixes
Moore, Anne K., The Christian Science Monitor
Just as your first tomatoes set and begin to swell, something collapses the bottom of the tomato, turning it to brown or black leather, or mush. The fruit is ruined. Go ahead and pull it off the vine. You can compost it, since a disease doesn't cause it. It's a weather- and gardener-related problem called blossom end rot. And there's an easy fix.
Tomatoes need calcium. A steady source of moisture helps them take it up. They need consistent water when mature, a quart a day, to ward off blossom end rot. If your tomatoes have succumbed to this, you can purchase and drench your plants with a calcium mixture made just for the problem. Or simply keep the plants watered, which will allow the vines to take up calcium again, and they should cure themselves.
Put mulch around the plants to hold moisture around the roots. And before you plant your next crop, check your soil's pH level and adjust it to between 6.0 and 7.0. Your local garden center can tell you what you need.
Big ugly green worms are also a common problem on tomato plants. Evidence of the pest may show up first as leaves eaten down to their ribs. On closer inspection, you may notice loose black dots (excrement) on your plants. Study the tops and bottoms of the leaves and stems and soon you will spot the culprit, a large hornworm.
There are two types of hornworms infesting gardens in the United States. Tomato and tobacco hornworms look similar but differ slightly in their coloring: The tomato hornworm sports a black- sided dark green "horn" on its backside; the tobacco hornworm has a red "horn." The white striping on their sides is also different, but it really doesn't matter which hornworm is eating your tomato plants. Either one can be found in your garden, and both can defoliate a tomato plant in days.
To control the pests, take a pail of soapy water to the garden, pull off the caterpillars, and drop them in the water. (If you are squeamish, wear gloves.) Mature hornworms are often quite large, 3- 1/2 to 4 inches long. …