Leafhoppers are destructive insects that are look similar to tiny grass hoppers. The insects typically only reach approximately 1/2 inch long and can jump rapidly from leaf to leaf. They eat the leaves of a variety of plants, which causes the leaves to curl upward and turn yellow along the edges. To effectively kill leafhoppers, you must kill both the adult insects as well as the larva that crawl on the bottom of leaves.
Examine the undersides of the leaves, especially ones that look curled or otherwise misshapen. Look for small, white, crawling larva which are baby forms of the leafhopper. Remove these larva using your fingers and squash them to kill them.
Spray the entire plant with an insecticidal spray that contains the ingredients resmethrin or permethrin, which are both effective against leafhoppers. Make sure to spray the tops and bottoms of the leaves as well as the entire stems to ensure complete coverage.
Wait 24 to 48 hours and examine the undersides of the plant leaves for signs of the larva or the adult leafhopper insects. If evidence of the insects is still seen, reapply a second dose of the insecticidal spray to the entire plant.