Lace bugs on azaleas
On azaleas the damage shows on top of the leaf while the bugs, their black spiny nymphs and their varnish-like excrement are all underneath. Spider mites are the usual confusion. Lacewing larvae eat the nymphs readily but seldom take adults, so a release only pays if it lands on the spring hatch; a specimen-garden trial that paired lacewing egg cards with water sprays suppressed two generations but took a lot of work. Part shade and layered planting help the resident predators do the same job for free.
At a glance
- Damage
- Bleached, silvery-stippled azalea leaves with black varnish-like spots underneath
- Type
- Sap feeding
- Settings
- Garden
- Threshold
- Aesthetic; act on first-generation nymphs if the shrub was damaged last year
- Release
- Chrysoperla carnea
- Rate
- Supplier rate of 2–20 /m² per release, weekly; no lace-bug-specific rate was found
How to confirm it
Turn a stippled leaf over. Lace bugs leave shiny black, varnish-like spots of excrement with cast skins stuck to them, and the adults have lacy, see-through wings held flat over the body. Spider mites stipple leaves too, but leave no black spots and sometimes leave fine webbing.
Identification, lifecycle, degree days and every control option are on the full Lace bugs profile. Not sure it is this pest? Answer four questions about the damage.
Work it out
How many do I need?
Carries Chrysoperla carnea and azalea & rhododendron through so nothing is re-entered. Open the calculator →