Be sure to apply lime two to four months before planting tomatoes. Apply the required amount of fertilizer based on soil test results for tomato. Following soil test recommendations is the best way to fertilize properly. Use mulches to conserve moisture. Use pinestraw, straw, decomposed sawdust, plastic or newspapers.
Mulches conserve soil moisture and reduce incidence of blossom-end rot.
Give your plants adequate water. Tomato plants need about 1.5 inches of water a week during fruiting. Extreme fluctuations in soil moisture can result in a greater incidence of blossom-end rot. Be careful with calcium chloride. If day temperatures are greater than 85-90 F , calcium chloride can burn plants.