 There's a lot of lab studies that show citronella can have a repellent effect, but those are lab studies with high concentrations of citronella, and we're not getting those same concentrations in the candles. And so while we're getting some out there, it's just not enough. So is there anything that will help keep our cookout reasonably free of mosquito bites? Kate says there is something we can do days ahead of the cookout. The best thing you can do is if there's any standing water on your property or around is dump it.