Many home gardeners grow tomatoes in their vegetable gardens. Some have self-inflicted problems that can be avoided by reading and following label directions when pesticides are being used.
The first issue we will discuss is damage to the top growth of tomato plants. We see two types of damage caused primarily by herbicide (weed killer) drift in home gardens. The first type of herbicide injury is caused by phenoxy herbicides used to control broadleaf weeds in lawns and other turf areas. I have seen this damage several times this spring and it causes the foliage of the plant to be irregular or twisted. It usually causes the end of the plant as production and growth will cease.
It is imperative that you READ, UNDERSTAND AND FOLLOW label directions when using all pesticides, especially herbicides used to kill weeds.
A second type of herbicide injury we are seeing is caused by products containing glyphosate that are non-selective products that kill everything they come into contact with. We commonly think of Roundup, but there are numerous products on the market containing glyphosate. This type of damage causes yellowing to the tomato plants foliage where the herbicide comes into contact with the plant. It can be caused by wind or other factors moving the herbicide off of the intended target and onto beneficial plants, such as tomatoes.
Remember to apply herbicides according to label directions, make sure the wind is not blowing and that temperatures are below 85 degrees.
It is important to remember that you need at least two backpack or potato pumps to insure that you do not cause this to your own plants. One sprayer should be used only for fungicides and insecticides and one should ONLY be used for herbicides. Always triple rinse your sprayer after each use.
Another problem we see related to tomato production is caused by poor pollination due to the cooler nights in the early spring. We call this symptom cat-facing as the fruit will take the appearance of a cats face and be somewhat malformed. This is common during the spring and will decrease when the night time temperatures increase.