Rules of Attraction

A Monarch Butterfly visits a marigold.

The heat of summer may already be upon us, but it’s not too late to add flowers and foliage to attract beautiful butterflies. The key is using sun-loving, drought-tolerant plants that appeal to hungry caterpillars and thirsty adult butterflies.

“Butterflies are solar-powered,” says Patricia Collins, who works for Georgia’s Callaway Gardens, home to one of the biggest butterfly conservatories in North America. “They love the sun.”

Start your butterfly garden by offering host plants like parsley, dill, anise and fennel for the caterpillars, the larval form of butterflies. You can find these edible herbs sold in 4- to 6-inch at nurseries and garden centers throughout the summer. If your garden soil has become dry and hard, plant them in window boxes, containers or raised beds, and water regularly. You’ll know your caterpillar buffet is a hit when you see nothing but stems one day, Collins says, laughing. “If you can’t stand a hole in a leaf, butterfly gardening isn’t for you.”

Caterpillars will also visit plants that may already be growing in your yard, including milkweed, clover and spice bush, and such trees and shrubs as willows, lilacs, tulip trees, aspens and elms. Just don’t use pesticides anywhere you want butterflies to visit.

After the caterpillars form cocoons, the emerging butterflies will need nectar. Collins suggests planting brightly colored zinnias, marigolds, salvias, butterfly weed and verbenas, which are heat-tolerant, nectar-infused, drought-resistant flowers with the short, tubular petals butterflies prefer. Plant masses of flowers to draw them, she says, rather than “onesies” and “twosies,” which are harder for the butterflies to see.

These butterfly-friendly flowers are ideal for beds or borders, but you can also buy them as dwarf or low-growing varieties to use in hanging baskets, pots and half-barrels. Again, water regularly. If your summers are really hot, try placing the plants in partial shade, or where they’ll get morning sun rather than hot afternoon sun.

Don’t be discouraged, Collins says, if you don’t see a lot of butterflies by July. From late summer into fall, successive generations begin to hatch, especially during warm, bright afternoons. As autumn gives way to winter, the monarchs start heading south. Until the cold weather arrives, “Just plant flowers and they’ll come,” Collins adds.