Butterflies aren't all that finicky about the flowers they visit, but their larvae are picky eaters. To have a great butterfly garden, it is important to provide lunch for the caterpillar.
From egg to adult, butterflies need the same things humans do: food, water, shelter and sunshine. You can encourage them to come to your garden by growing colorful flowers for the adults and a few plants that caterpillars are welcome to nibble on.
Pam Thomas, horticulturist at Garden in the Woods in Framingham, Mass., the garden of the New England Wild Flower Society (www.newfs.org), teaches classes on butterfly gardening. She divides her butterfly-gardening plant list into host plants and nectar plants to accommodate butterflies at every stage of their lives.
"Good butterfly gardens aren't just a collection of plants, they're an environment," Thomas says.
Butterfly gardening is easy. Many plants attractive to butterflies and caterpillars don't need much pampering. Some of the simplest and most sensible choices are native plants, which are very tolerant of local conditions. Caterpillars also eat crabgrass, clover and violets, and most gardens have plenty of each to spare.
At the height of summer, you may see dozens of butterflies in the garden at once, sipping nectar from purple coneflowers, bright zinnias, pentas, lantanas, verbenas, salvias and old-fashioned hollyhocks. A good variety of plants will attract the greatest diversity of butterflies.
Butterfly weed (Asclepias tuberosa) is one of the best-known and most dependable host plants for the larval stage of the monarch butterfly. The adult butterflies lay their eggs on these plants, and in late summer, voracious caterpillars -- with fantastic yellow, green and white stripes -- hatch out and begin to devour the foliage.
All they do is eat and sleep, and they grow at an astonishing rate. They may consume every leaf they can reach, but the plants always survive and come back the following year. To hide the damage, plant butterfly weed among other flowers, such as asters or bee balm, which will fill in around the butterfly weed during caterpillar season.
If you keep a sharp eye out, you may be able to spot the opalescent chrysalis of the monarch butterfly hanging from a twig or a leaf. When they emerge from their chrysalises, the new butterflies like open spaces to fly around in and flowers big enough to land on easily. A wall or a few evergreen shrubs will offer shelter from the wind, and a few flat rocks will provide a place for the butterflies to sun themselves. A shallow, ground-level birdbath or a small water garden complete the backyard butterfly habitat.
Thomas usually takes her classes to the meadow area at Garden in the Woods to learn to identify butterflies and the plants they prefer. It's open and sunny, as a butterfly garden ideally should be. "The larger the area the better," Thomas says, "but you can do it on a small scale, too."
To really appreciate butterfly gardening, it's a good idea to have a bench in the garden, says Andrea DeLong-Amaya, gardens manager at the Lady Bird Johnson Wildflower Center in Austin, Texas (www.wildflower.org). The center's large butterfly garden provides a habitat for hundreds of different butterflies. Paths meander through a meadow, along a woodland edge and up a streambed to a shaded spring.
Since butterflies are insects, they are extremely sensitive to pesticides, which should never be used in their vicinity. In a thriving, diverse garden, pest populations rarely get out of control, anyway, because natural predators, including birds, also find such places attractive and help to keep them in check. Butterflies are a sign of a healthy garden.
Butterfly garden ideas
You can incorporate butterfly plants into existing flowerbeds or make a new butterfly garden in a sunny spot. You really should have a garden bench so you can take your time and get to know the butterflies.
Here are some sources for ideas, and the names of some plants that provide food for caterpillars and nectar for adult butterflies and are easy to grow.
* Botanic gardens, county extension offices, native plant societies and conservation organizations are helpful sources of information about butterfly gardening and the native plants you should plant to attract local species. The "Grow Native!" program developed by the Missouri Department of Conservation has published a plant list and an easily adaptable design for a butterfly garden on its Web site: www.grownative.org. The plan and list would be appropriate almost anywhere in the country.
* Great-looking flowers that butterflies love: asters, coneflowers, phlox, butterfly bush, sunflowers, verbenas, zinnias.
* Host plants for butterfly larvae: dill, parsley, hackberry, native grasses, spicebush, butterfly weed, viburnums, wisteria.