Planthopper nymphs are numerous but scattered on plants at this time. Affected hosta, fuchsia, and other plants (particularly in shady areas) will have a white, cottony material on the stems and petioles. Under this flocking will be a whitish or greenish planthopper nymph that is 1/8 to 1/4 inch long. These insects feed on the sap of the plant and can kill the stem beyond their feeding point. Some species also are present as adults; these are about 1/4 inch long with wide, tall, wings. The most common species are white, green, and purple with white markings. Adults usually do not cause dieback. Planthoppers can be controlled with insecticidal soap, summer spray oil, and synthetic pyrethroids. At home, I handle these with a spray bottle containing insecticidal soap. One or two squirts usually does the job.
Leafhoppers transmit aster yellows to marigolds and other flowers. Leaves on infected plants tend to wither, turn brown, and die. The plant dies a slow death and the brown, shriveled leaves are ugly to passersby. Because very few leafhoppers need to be present to transmit the disease and are present for an extended period of time, many landscapers just replace infected plants as they appear, rather than use insecticides.