By high summer the gardens are in full bloom and exploding with color--purple and sky-blue asters, orange butterfly flowers, and purple coneflowers. Just a stone's throw from downtown Minneapolis flourishes the nation's oldest public wildflower garden. Established in 1907 by transplanted Easterner Eloise Butler, who feared the city would eventually gobble up the local flora and fauna, the garden has over 400 species of wildflowers in three habitats--prairie; woodland, and bog. The first to emerge is the woodlands-- ostrich and maidenhair ferns, trillium, bloodroot--while heat-loving black-eyed Susans and goldenrods peak just as the dog days burn to an end. The bog is a tangle of tamarack, moss, and ferns that yields an occasional burst of color with the appearance of pink swamp milkweed and blue flag iris. There's no charge--and no smoking. Open from 7:30 a.m. until dusk, April 15 through October 15.