Pests to know in Wilmington
Termites in Wilmington
Soil termite treatments in Delaware have to be done on-site by a certified commercial applicator who holds the wood-destroying pest category, known as 7B.[8]
Invasive species reported here
- Delaware's first spotted lanternfly turned up near Wilmington: state inspectors found a single dead one in the area in 2017.[7]
- Spotted lanternfly populations are now confirmed in all three Delaware counties, and the quarantine covers the whole state, so items moved outdoors should be checked for egg masses.[7]
Pests local experts flag
Delaware officials call the Asian tiger mosquito the state's toughest nuisance mosquito. It stays within roughly 300 feet of where it breeds, so biting usually means a water source is nearby.[2]
Climate
Central Wilmington (ZIP 19801) is in USDA plant hardiness zone 7b, where the average coldest winter night is 5 to 10°F.[10]
Public agencies that handle pests
- DNREC's Mosquito Control Section runs a northern field office in Glasgow that handles nuisance mosquito calls for all of New Castle County, which includes Wilmington.[1]
- For mosquito spraying, the state is split into 216 numbered spray zones. Residents can sign up for alerts when their zone has planned truck or aerial treatments.[3]
- DNREC's tick program surveys ticks and the germs they carry across Delaware all year. It has documented the invasive Asian longhorned tick in New Castle County.[4]
- State health officials say blacklegged (deer) ticks live in every Delaware county, and this is the only tick species there that spreads Lyme disease.[5]
- Raccoons are the most common rabies carrier in Delaware. Among domestic animals, feral cats are the ones most often diagnosed.[6]
Hiring a licensed company
In Delaware, any business that applies pesticides to someone else's property must hold a state certification and a Pesticide Business License from the Department of Agriculture.[8]
Free local help
University of Delaware Extension notes that the invasive box tree moth may have two to three generations a year in Delaware. Overwintered caterpillars start feeding on boxwoods in late May to early June.[9]
Through the year
- Winter to Fall
- Lanternfly egg masses survive Delaware winters and hatch in late April or early May. Adults die off after a hard fall frost.[7]
Sources
- Delaware DNREC, Division of Fish and Wildlife, “Mosquito Control.” dnrec.delaware.gov/fish-wildlife/mosquito-control/ (accessed 2026-10-06)
- Delaware DNREC, Division of Fish and Wildlife, “Asian Tiger Mosquitoes.” dnrec.delaware.gov/fish-wildlife/mosquito-control/asian-tiger-mosquitoes/ (accessed 2026-10-06)
- Delaware DNREC, Division of Fish and Wildlife, “Mosquito Spraying.” dnrec.delaware.gov/fish-wildlife/mosquito-control/mosquito-spraying/ (accessed 2026-10-06)
- Delaware DNREC, Division of Fish and Wildlife, “Ticks.” dnrec.delaware.gov/fish-wildlife/ticks/ (accessed 2026-10-06)
- Delaware Division of Public Health, “Lyme Disease.” dhss.delaware.gov/dph/homepage/about/sections/ehdishome/epi/lyme/ (accessed 2026-10-06)
- Delaware Division of Public Health, “Rabies.” dhss.delaware.gov/dph/homepage/about/sections/ehdishome/epi/rabies/ (accessed 2026-10-06)
- Delaware Department of Agriculture, “Spotted Lanternfly.” agriculture.delaware.gov/plant-industries/spotted-lanternfly/ (accessed 2026-10-06)
- Delaware Department of Agriculture, “Pesticide Management FAQs.” agriculture.delaware.gov/pesticide-management/faqs/ (accessed 2026-10-06)
- University of Delaware Cooperative Extension, “Box Tree Moth.” www.udel.edu/academics/colleges/canr/cooperative-extension/fact-sheets/box-tree-moth/ (accessed 2026-10-06)
- USDA ARS and PRISM, via phzmapi.org, “Plant hardiness zone for ZIP 19801 (2023 USDA map data).” phzmapi.org/19801.json (accessed 2026-10-06)
- National Pesticide Information Center, “State Pesticide Regulatory Agencies.” npic.orst.edu/reg/state_agencies.html (accessed 2026-10-06)