Tomatoes and the Drought

Steve Allgeier
Carroll County Master Gardener

A recent influx of tomato problems provided the inspiration for this week's article. The growing season has been particularly difficult for the gardener especially the tomato gardener. We have had erratic spring temperatures, little summer precipitation, and hot grueling stretches. What's next? I don't know (hopefully some rain). Compounding all of this is the fact that watering restrictions are getting tighter and tighter.

The tomato problems will become more severe as the summer progresses. Tomato plants can suffering from a condition known as "Blossom-End Rot". This is a physiologic disorder associated with a lack of calcium. The fruit on the effected plants develops a dark soft bottom that enlarges as it ripens. This disorder is caused by insufficient calcium in the soil or too much or too little soil moisture. Most of the problem can be attributed to lack of moisture. It is best to pick off any fruit that is showing symptoms and spray the foliage with a calcium chloride solution and water deeply (if you can). You can usually find these calcium chloride sprays in your garden center.

The other reoccurring problem to cross my desk is spider mites (and they can effect plants other than tomatoes). These particular pests are serious trouble in hot dry weather. Their populations grow explosively when it is hot and dry, and they can kill a plant quickly. Spider mites are extremely small 8-legged bugs that are typically found on leaf undersides. They feed by piercing the leaf and withdrawing the plant fluid. Heavy mite infestations will yellow and then eventually brown the leaves of the plant. The best control is early treatment, before infestations are too heavy, with a registered pesticide.

Be careful when using these pesticides, they can easily damage tomato foliage in this heat. An alternative that many people find effective is to use a strong stream of water to knock the mites off the plant.

Read other articles by Steve Allgeier

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