By Barbara Pleasant, Calmful Living Gardening Editor
Butterfly babyhood is pretty secretive business, but everything changes when caterpillars emerge as butterflies, the peacocks of the insect world. Sporting bright colors in splashy symmetrical patterns, butterflies make no attempt to hide as they sip flower nectar on warm summer days.
If you’d like to see butterfly births happening in your yard, you can create a butterfly habitat by growing a few selected plants and then letting caterpillars eat them. Then train your eyes to find the pebbly trails of “frass” that are the clear evidence of caterpillar feeding, and watch for cocoons attached to tall stalks of grass or fences. The process will cause some tattered and rolled leaves, but that’s part of the fun of bringing up baby butterflies.
Adult butterflies will then sip nectar from hundreds of plants, but their home garden favorites are bee balm (monarda), butterfly bush (buddleia), lantana and zinnia.
Here are eight easy-to-grow host plants that serve as food for common North American butterflies:
Aspens and poplars are much loved by a long list of butterflies, from white admirals to mourning cloaks. If you need a reason to keep an aspen or poplar in your yard, baby butterflies may be it.
Apples that are not sprayed with pesticides are likely to see a little action from spring azures and viceroys, but the caterpillars will not eat enough leaves to weaken the trees.
Butterfly weed is a favorite of monarchs, and there are two well-behaved native species for different garden niches. The common orange-flowering form (Asceplias tuberosa) is ideal for sunny spots, but consider white-flowering swamp milkweed (Ascepias incarnata) for moist soil in partial shade.
Carrot family members, including parsley, dill and carrots, are food plants for eastern black swallowtails and anise swallowtails. It is worth sacrificing a plant if you find one of these showy green-and-orange caterpillars in your carrots.
Clovers of all types and colors support bright yellow sulphurs and orange sulphurs, especially when clovers and other legumes grow among tall grasses. When the small green caterpillars finish feeding in the clover, they climb up the grasses to pupate.
Hollyhock leaves that are being eaten by a big, bristly caterpillar are supporting a painted lady, which are increasingly rare. Tan caterpillars feeding on hollyhocks mature into checkered skippers.
Violets will cease to be weeds to you when you see orange spangled fritillaries gracing your garden on summer days. In addition to feeding fritillary larvae (the black, spiny caterpillars feed at night), clumps of violets help insulate overwintering caterpillars from cold.
Willow leaves that are being eaten by bristly black-and-orange caterpillars have been discovered by mourning cloaks. Bumpy brown caterpillars feeding on willow will hatch into viceroys.
Who are the butterflies in your yard? To narrow down the list of possibilities, go to butterfliesandmoths.org and click “regional checklist.” Fill in your country, then state and county, then hit “apply.” Now you have a list of butterflies and moths to look for in your garden.
The best way to make a difference to threatened butterflies is to become a good host to one. The Xerces Society maintains a Red List of butterflies and moths in need of conservation efforts.
Barbara Pleasant is not just an expert, she’s passionate about everything garden. She’s the author of four books, including Starter Vegetable Gardens: 24 No-Fail Plans for Small Organic Gardens and is a contributing editor to Mother Earth News and the Herb Companion magazines. Her work has garnered her multiple awards.