One of the best ways to encourage butterflies in your garden is to grow food plants for caterpillars. Adult butterflies spend their short lives looking for mates and laying eggs. Where better to congregate than in a garden where their offspring can hatch and grow safely to adulthood? Nectar-rich flowers feed them while they search, so plan your garden to satisfy both needs.
Violets, pansies, and Johnny-jump-ups feed the young of many fritillary species. Drifts of these hardy, sweetly scented flowers attract the dramatic, 3-inch-wide great spangled fritillary as well as smaller meadow fritillary and their intricately patterned relatives. New England aster (Aster novae-angliae) and related species host the caterpillars of butterflies such as clouded sulfurs, checkered whites, and pearl crescents. Many adult butterflies, especially the monarch, depend on its abundant nectar for energy in late summer and early autumn. Other important late-season nectar sources include zinnia, marigold (Tagetes spp.), goldenrod (Solidago spp.), Joe Pye weed (Eupatorium spp.), and sedum (Sedum spectabile).
To encourage the widest variety of butterflies, let your garden go wild around the edges; leave room for wild grasses, clover, nettles (Urtica spp.), willows, sassafras, and milkweed (Asclepias spp.). Thickets, marshes, meadows, and wooded edges provide the rich habitats that butterflies call home.