Herbicide Damage on Tomatoes

Herbicide Damage

• Curling leaves are early signs that your plant has been sprayed with an herbicide, according to Iowa State University. Young leaves may narrow and begin pointing downward from the plant, according to Oklahoma State University. Eventually, the stems twist, split and are brittle. There may discoloration or tomatoes without seeds. These symptoms occur all over the plant, which sets them apart from fungal disease manifestations.

Injury-Causing Herbicides

• Phenoxy herbicides, such as 2,4-D and dicamba, cause tomato plant damage, according to Oklahoma State University. Herbicides containing glyphosate also cause herbicide injury. Glyphosate prevents protein production in the tomato plant. Signs that glyphosate was sprayed on your tomato plant include a yellowing at the base of leaflets, according to North Carolina State University. Other broad-spectrum herbicides and post-emergent sprays for the lawn also harm tomato crop.

Spraying Herbicides

• When spraying around tomato plants, cover them with plastic and secure it with a brick. Remove the plastic after spraying, or you may suffocate the plants. Don't spray on a windy day, as the spray drifts on the wind. Remove weeds growing next to your tomato plants by hand rather than using herbicide. Apply herbicides with a paintbrush directly on weeds rather than spraying.

Other Considerations

• Gardeners harm their tomato plants by touching them with anything that has herbicide residue. These items include rakes, spades, gloves or shovels. Wash your gloves after handling herbicide spray. Herbicide residue on clothing harms tomato plants, according to North Carolina State University. Avoid using chemically treated grass clippings as mulch. Other lawn products, such as lime, fertilizer and pre-emergent herbicide spray, may harm your tomato crop.