German Cockroaches: How to End an Infestation

Confirm it is German

Small (13–16 mm), tan, two dark stripes behind the head, loves kitchens. American roaches are bigger and prefer basements and sewers. Treatment differs — identify first.

The fogger trap

Foggers feel productive and fail. Studies show bait + sanitation + sealing clears apartments in 2–4 weeks while fogged units stay infested. Save the money and the cleanup.

Apartment realities

Roaches travel through shared walls. Tell neighbors and the landlord, bait your unit, seal pipe chases with copper mesh and caulk. Building-wide baiting beats solo spraying.

When to call a pro

Heavy infestation (droppings everywhere, daytime sightings), asthma in the home, or no drop after 2 weeks of correct baiting. Pros rotate bait actives to beat resistance.

How to: German Cockroaches: How to End an Infestation

Two-week German roach knockdown.

You'll need

• gel bait (fipronil or indoxacarb)
• sticky monitors
• caulk
• airtight bins

Tools

• vacuum with crevice tool
• flashlight

1. Vacuum and monitor

   Vacuum behind fridge, stove, dishwasher and under sinks. Place sticky monitors to find hot spots.

2. Bait the harborages

   Apply pea-sized gel dots inside cabinet hinges, under appliances and along pipe chases. Refresh weekly.

3. Dry and declutter

   Fix leaks, run the fan, seal food in bins, pull trash nightly. Remove cardboard harborage.

4. Seal and follow up

   Caulk crevices after activity drops. Keep monitors 30 days; re-bait any renewed activity.

Frequently asked questions

Do bug bombs work on roaches?

No. Foggers repel roaches into walls and leave pesticide on counters. Baits outperform them in every study.

How fast do German roaches multiply?

One egg case holds 30–40 nymphs and hatches in a month. Small sightings become hundreds fast — act early.

Photo credits

Thank you to Oliver Ren for sharing this beautiful photograph and helping bring this guide to life.

Wikimedia Commons