Smolder Coffee Grounds in a Foil Bowl to Push Mosquitoes Off the Porch

The Problem

Mosquitoes own the porch at dusk, citronella candles are perfume with marketing, and nobody wants to mist the patio with insecticide before dinner. Smoke genuinely repels mosquitoes — the question is a smoke source that's cheap, controlled, and doesn't smell like a tire fire.

The Technique

  1. Fold a small bowl out of aluminum foil (or use any oven-safe dish — it will get hot).
  2. Put in about two teaspoons of coffee — used grounds work once they're completely dry.
  3. Light the grounds with a lighter until they start to smoke, then let them smolder. No flame needed once it's going — the smolder is the product.
  4. Set the bowl on the porch, by the campsite, wherever you want the mosquito-free pocket. The creator's experience: a smolder that runs for hours and clears a radius around the seating area. Reload as needed.
  5. If the grounds won't light or won't stay lit, pour a little 91% isopropyl alcohol over them and light that — it kickstarts the smolder.
Pro tip: Treat the range claims as a starting point, not a spec — smoke drifts, so put the bowl upwind of where people sit and let the plume do the covering. Two small bowls bracketing the seating beat one big one.
Safety note: This is a live ember in a very light container. Outdoor use only, on a non-combustible surface, away from anything that blows or burns — and douse it when you go in. The alcohol goes on before lighting, never onto grounds that are already burning.

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