The Memphis Botanic Gardens has a lovely butterfly garden:
I did see a lot of butterflies, but they were flying higher than I could get pictures of. There were also bees and dragonflies.
Even though it's been here a while, I think of it as one of the newer features. It gets better every year. The Botanic Gardens web site has this description:
Today, the Butterfly Garden incorporates a variety of plants designed to attract butterflies. A major portion of the plants are native. The large variety of herbs in this garden, including parsley, fennel, and chives, acts as food for butterfly larvae. Many species, such as coneflower, goldstrum daisies, asters, and joe pye weed, serve as sources of nectar. Passion vine and red honeysuckle, known as "Mardi Gras," grace the arbor with color and fragrance.