I hesitate to say this for fear of tempting fate, but so far in this part of the Languedoc (Herault) wasps haven't been more of a problem than in other years. Now I'm worried though. On citronella candles, I've read that they're no more effective at keeping away flies & other insects than any other kind of candle--just more expensive. Good luck, I can imagine that an army of aggressive wasps wouldn't do much to enhance summer dining outdoors.