Projects like installing new carpet and painting walls can release chemicals that pollute indoor air. Luckily, some houseplants moonlight as efficient purifiers. For the best results, put as many plants as you can care for in the rooms you use most, says environmental scientist Dr. Bill Wolverton. That means you'll want at least two plants (in 10- to 12-inch pots) per 100 square feet of space; if you're in the middle of major renovations, aim for more plants. One tip: Be sure not to overwater, as too much soil moisture can lead to mold growth.
Here are 10 smart options you can buy at your local nursery. To learn more, pick up Wolverton's new book, "Plants: Why You Can't Live Without Them" (Roli Books; $25).