Tricks for preying on their weaknesses:
Get rid of standing water. “That’s where mosquitoes breed,” says Laura Harrington, an associate professor of entomology at Cornell University. “The week before the party, empty out the kiddie pool, the rain gutters, and any rainwater that has collected in the bottoms of flowerpots.”
Plug in some fans. “Mosquitoes are weak flyers, so even if a fan is set on low, it can create enough airflow to keep them away,” says Harrington. This works best in a small area, like a deck, where you can set up two or three box fans around your guests. It’s also a good idea to put a tabletop fan near the salads.
Offer guests bug wipes that won’t create a smelly fog. “Look for products that contain the repellent picaridin instead of DEET,” says Harrington. “DEET can degrade synthetic fabrics, damaging clothing.” Try Skin So Soft Bug Guard Plus Picaridin Towelettes ($14 for eight, avon.com); stash them in a basket by the back door. You might also consider a bug-repellent gadget for the yard; for the most effective options, see The Best Insect Repellent Options.