Different species of butterflies like different types of flowers. If you intersperse groups of both wild and cultivated plants, as well as bloom times (time of day as well as year), you will bring the greatest numbers and variety of butterfly visitors. Large plantings of the same plants will be easier for butterflies to see than singly planted flowers. Some varieties of flowers which are easy to find and grow in Illinois, and will be attractive to many types of butterflies include: Aster, Black-eyed Susan, Coreopsis, Day lilies, Goldenrod, Hibiscus, Lavender, Lilac, Marigold, Butterfly Bush, Ox-eye Daisies, Phlox, Pink Azalea, Purple Coneflower, Redbud, Rosemary, Verbena. Here are some common butterflies and their food plants and host plants:

American Painted Lady - Borage, Burdock, Everlasting,
Hollyhocks, Knapweed, Mallow, Sunflower, Wormwood

 
Great Spangled Fritillary - Violets, Pansy, Spear Thistle
(Cirsium vulgare)  Wild Bergamot (Monarda fistulosa)

Gulf Fritillary - butterfly bush
 

Variegated Fritillary
 

Black Swallowtail - Carrot, Dill, Fennel
Parsley, Queen Anne's Lace, Rue

Cabbage White - New England Aster for nectar
Host plants:  Violets, Broccoli, Cabbage, Mustard, Nasturtium

                              
Dwarf Yellow - Violets

Common Wood Nymph - Wild Bergamot (Monarda fistulosa) Ox-eye Daisy, Frost Aster

Butterfly Anatomy
Adult butterflies and moths have mouth parts shaped into a long, coiled tube. Forcing blood into the tube straightens it out, allowing butterflies to feed on liquids. Butterflies get all their food from this tube, which limits them to nectar and standing water. Larvae, on the other hand, have chewing mouth parts which they use to skeletonize or totally defoliate leaves. Butterflies have large, rounded compound eyes which allows them to see in all directions without turning their head. Like most insects, butterflies are very nearsighted, and are more attracted to large stands of a particular flower than those planted singly. They do not see "red" as well as we do, but they can see polarized light as well as ultraviolet light, which is present on many flowers and guides them to nectar sources. Butterflies also have a very well-developed sense of smell from their antennae. All butterflies' antennae are club-shaped, as opposed to moths, which can be many shapes but often are feathery.

Butterflies begin their life as an egg, laid either singly or in clusters depending on the species. A caterpillar emerges and, after consuming its egg shell, begins feeding on its host plant. Caterpillars must crawl out of their skin or molt, usually around five times, before changing into a pupa. Finally, an adult butterfly emerges, spreads its wings and flies away. This type of development is complete metamorphosis.

Butterfly gardens are a great source for your own enjoyment, photo opportunities, or an outlet for artistic talent. These gardens can also be extended to interest youth in nature, by providing a small window of native inhabitants of the local environment. On a final note, it's important to conserve butterflies when possible since their habitat is constantly diminishing due to the increasing needs and consequent development of roads and housing.