From the Vegetable Gardener, a really great list of plants for supporting bees and butterflies. If you plant a vegetable garden, have an herb garden, or have fruit trees, this idea will not only benefit you, but also you local bee and butterfly population.
health benefits have been proven time and time again.
As if all of those things weren't enough, many herbs produce flowers that are completely irresistible to pollinating insects, as well as an unlimited number of wildlife species including native bee species, honey bees, butterflies, and hummingbirds. Complement your vegetable garden some polliantor-seducing herbs.
Butterflies are the happiest in sipping on flowers planted in areas with good sun and little or no wind.
Check out the Vegetable Gardener's site for the rest of the list, including plants for hummingbirds!