Farm Advisor: Summer Tomato Problems

This article was provided to MyMotherLode.com by Calaveras County Farm Advisor Ken Churches.

San Andreas, CA -- Summer is the time when we all look forward to those great home grown tomatoes. Unfortunately, heat can make your tomato plants look very discouraging at times. The most common tomato problems that we receive calls on are described here:

- Blossom drop: It is usually caused by dry soil and dry winds, but also may be caused by a sudden cold spell or too much nitrogen. Usually not all blossoms will fall off, so be patient for the next set of flowers.

- Blossom end rot: The end of the fruit furthest away from the stem gets black – a condition caused by irregular watering practices and calcium deficiency. Water deeply and regularly. Add lime to soil in fall to increase calcium level in the soil for next year´s crop. It is a cosmetic problem, but most of the tomato is still edible.

- Leaf rolling: A problem that is most often the result of heavy pruning or root injury. Plants may lose leaves but will recover.

- Sun scald: Green tomatoes can get sunburned, especially those plants with leaf spot diseases or those recently pruned.

- Early and late blight: These are fungal diseases. Look for water-soaked looking spots on lower leaves and stems. If you see these, pick them off. Avoid overhead watering and monitor and remove diseased leaves.

This article adapted from Cooperative State Research, Education and Extension Service, USDA. Please contact the Farm Advisor´s office at (209) 754-6477 with your agricultural questions. Talk to a certified Master Gardener every Wednesday from 10 a.m. to 12 p.m. at (209) 754-2880.

Ken Churches is the county Farm Advisor and director for the University of California Cooperative Extension.