Push the soil up on the side away from the roots to form a pillow for the top of the plant encouraging a straight start. Problems occur with sudden changes in soil-moisture levels. Below are several problems that tomato plants develop because of poor growing practices or nutritional imbalances. A low level of calcium available to the plants is the reason for blossom-end rot. It may be that your soil is deficient in calcium, adding organic soil amendments will solve this problem by adding the needed nutrients in a slow release manner that the plant can use over the growing season.
Heavy rains can also cause the lack of calcium, washing valuable nutrients out of the soil.
Be sure to mulch your tomatoes with about 4 inches of oat straw or marsh hay. This will even out the moisture levels in your soil and help to protect the soil from nutrients leaching out. Catfacing Misshapen fruit has black scarred areas on the blossom. Catfacing happens when flowers don't develop properly. The most common cause is low temperatures below 65F during the day and 55F at night three weeks before flowers open.