Backyard Grapes Identify & treat grapevine problems
Insect / pest high severity

Spotted lanternfly

Lycorma delicatula

An invasive planthopper that swarms vines, sucking sap and coating them in sticky honeydew and sooty mould.

Spotted lanternflies feeding on a grapevine, on the canes and around the clusters Photo: Erica Smyers, Penn State Penn State News
Heavy infestation of adult spotted lanternflies on a grapevine trunk beside ripening clusters Photo: Penn State Penn State News CC BY-NC-ND 4.0
First instar spotted lanternfly nymphs on the underside of a young grape leaf Photo: Heather Leach Penn State Extension

Description

The spotted lanternfly is an invasive planthopper from Asia that has spread rapidly through parts of the eastern United States, and grapes are among its favourite crops. Large numbers pierce the vine to feed on sap, weakening it, reducing yield, and leaving vines less able to survive winter. Unlike many pests it attacks the woody parts as well as the foliage, blanketing trunks and cordons.

Their feeding produces enormous amounts of honeydew, which drips over the canopy and fruit and grows black sooty mould, fouling the crop. Management combines destroying the distinctive mud-like egg masses in winter, removing the tree-of-heaven that fuels populations, trapping climbing nymphs, and spraying under heavy pressure. In regions where it hasn’t been seen before, reporting it early helps slow the invasion.

What to look for

  • Masses of grey-and-red winged planthoppers, plus black-and-white then red spotted nymphs, on trunks, cordons, and shoots.
  • Weeping sap, wilting, and loss of vigour and winter hardiness after heavy feeding.
  • Sticky honeydew on leaves and fruit that blackens with sooty mould.
  • Grey, mud-like egg masses on trunks, posts, and nearby surfaces.

Treatment options

Cultural & prevention

Start here — habits that stop problems before they spread.

  • Scrape and destroy egg masses on trunks and posts through winter.
  • Remove nearby tree-of-heaven, its favoured host, or use it as a trap plant.
  • In newly invaded areas, report sightings to local agriculture authorities.

Organic / low-toxicity

Gentler sprays and biologicals for active outbreaks.

  • Circle/sticky traps on trunks catch climbing nymphs (screen them to spare birds).
  • Insecticidal soap or horticultural oil knocks down nymphs on contact.

Conventional fungicide / pesticide

For severe cases. Always follow the product label.

  • Contact and systemic insecticides labelled for spotted lanternfly during heavy pressure, respecting pre-harvest intervals.

Sources

This entry is based on the references below. Read them for full detail and for spray timings and rates valid where you live.

  1. Spotted Lanternfly Management in Vineyards — Penn State Extension
  2. Spotted Lanternfly in Virginia Vineyards: Lycorma delicatula (White) — Virginia Cooperative Extension (Virginia Tech)
  3. Pest alert: spotted lanternfly in grape production — Ohio State University Extension (CFAES Knowledge Hub)
  4. Spotted Lanternfly (SLF) II - Scouting and Management — University of Maryland Extension