To attract butterflies, design a garden that provides a long season of flowers that provide nectar. Perennials, such as chives, dianthus, bee balm, butterfly weed, black-eyed Susan, and echinacea, offer a succession of blooms. Add annuals such as cosmos, petunias, and zinnias, that flower all season. Flowers with many small tubular flowers or florets—liatris, goldenrod, and verbena, for example—or those with single flowers, such as French marigold, Shasta daisy, and sunflower.