The tomato is a favorite plant in most Alabama vegetable gardens. Even people who don't plant a garden often have a tomato bush or two planted at home.
Because tomatoes are such a favorite, people want to grow large quantities of high quality fruit on tomato plants. Blossom end rot is a problem that disrupts growth of the tomato fruit. It begins as a small, sunken, dark brown leathery spot on the blossom end of the fruit.
But you can take measures to prevent blossom end rot from occurring on your tomatoes. First, understand that blossom end rot is a physiological problem-not a disease. It occurs when tomato plants are unable to take up sufficient calcium to mature fruit properly. The problem most commonly expresses itself during periods of fluctuation in soil moisture.
This inability to take up calcium may occur for several reasons. First, the pH of the soil your tomatoes are planted in may be too low. The optimum pH range for tomatoes is 6.0 to 6.8. Soil test to determine the soil pH and apply dolomitic lime at the recommended rate. It takes several months to adjust soil pH. So even if you've already planted tomatoes this year, you may want to soil test for next season.
Drought stress will also limit tomatoes' ability to take in calcium. Regular watering and mulching of the plants will help you prevent this problem. Pine straw, wheat straw and newspaper are all good choices of mulch. If you use newspaper, use landscape pins or cover it with straw to hold it in place and keep the garden attractive.
If your soil is too moist, tomato plants can have difficulty taking up calcium. Using raised beds and amending the garden soil with plenty of organic matter will improve drainage and help reduce excessive moisture in some situations.
Applying too much fertilizer at one time can also encourage blossom end rot on tomatoes. Be sure to follow soil test and planting recommendations.
If your plants do develop blossom end rot, there are calcium chloride and calcium nitrate sprays you can apply. These sprays require two to three applications per week to be effective. Calcium chloride sprays can burn plants if the temperature is greater than 85 degrees Fahrenheit when the spray is applied.
In general, it's easier and cheaper to take steps early to prevent blossom end rot in tomatoes than it is to treat the problem once it shows up on your tomatoes.
