Lace bugs
Small flat insects with lacy wings that feed under leaves, leaving the upper surface speckled pale and the underside spotted with black.
Also known as: Lacewing bugs
Symptoms and identification
Upper leaf surfaces become finely speckled with white or yellow dots, giving a bleached look. Undersides carry small, sticky black spots of excrement, cast skins and tiny insects with lace-like wings.
Causes
Lace bugs thrive in hot, dry weather and on plants in full sun with poor airflow. They overwinter as eggs inside leaf tissue.
Organic treatment
Hose leaf undersides with water to dislodge bugs, then spray neem oil or insecticidal soap every week for three or four weeks.
Prevention
Keep plants well watered and mulched, avoid placing sensitive plants against hot walls, and check leaf undersides in dry weather.
Chemical treatment (use with care)
Use an insecticide labelled for lace bugs, applied to leaf undersides, following the label.