Planthopper nymphs on a stem
Planthoppers look like large leafhoppers and have similar feeding habits. They may also be known as flugorids and lanternflies. A common planthopper is one of the flatids which is wedge-shaped, flattened and pale green. Planthoppers feed on plant juices and produce honeydew. They feed on a wide variety of herbaceous ornamental plants but cause little damage. They are generally noticed because of the white waxy material produced by the nymphs (see photo above). The nymphs are covered by the waxy material and may also leave some behind on the stems of plants they are feeding on.
Close up of planthopper nymph
with waxy covering and residue
Closeup of planthopper nymph
No control is necessary. However, you can wash it off the stems of your plants with a stream of water.