What if I told you the secret to a beautiful wildlife garden was a bunch of hungry caterpillars?
That's actually the concept that garden designer Sarah Konradi promotes through her job with the Natural Learning Initiative at N.C. State's College of Design.
When I called Konradi to talk about attracting butterflies to my wildlife garden, she started out by explaining the life cycle of these most beautiful of arthropods.
"The perception most people have of a butterfly garden is to focus on plants that will attract adult butterflies," Konradi says. "But we also like to emphasize the growing trend for keeping the entire life cycle in mind, since it's the butterfly's main task in life to create babies."
Butterflies go through four developmental stages, starting with an egg, which hatches into a caterpillar, which evolves into a chrysalis, then finally emerges as the colorful butterfly we delight in seeing in our gardens.
Konradi and other experts argue that it is important to support all the life cycle phases of butterflies, not just the adults, or one day there may be no more butterflies to attract. For example, she points to the migrating monarch butterfly, whose numbers have dropped dramatically in the past decade largely due to eradication of milkweed, a plant that is preferred food for Monarch caterpillars.
In addition to monarchs, some types of butterflies commonly seen in our region are tiger swallowtails, sulphurs, skippers, hairstreaks and buckeyes, which together will bring brilliant dashes of color to your garden.
Most species of butterflies do not migrate but live out their lives in relatively small areas where they can find specific types of food needed to reproduce and thrive. Butterfly eggs are laid on a "host plant" that becomes sustenance for the growing caterpillar after it hatches from the egg in just a few days.
Thus, having the preferred host plant is key to encouraging more caterpillars - and butterflies - in the garden.
Preferred hosts vary with butterfly species, but native species are recommended. In our area, the list might include Lindera benzoin (spicebush), Eupatorium fistulosum (Joe-Pye weed), Helianthus atrorubens (sunflower), Ruellia caroliniensis (Carolina wild petunia), and Baptisia tinctoria (wild indigo).
Konradi urges groupings of several similar types of host plants.
"It's OK to use a diversity, as long as you plant three to five of each kind, because they will attract different kinds of butterflies to lay their eggs," she says.
Eggs will hatch in a few days, and the caterpillar stage lasts 10 days to two weeks. Caterpillars eat constantly while growing from the size of a pinhead to more than 2 inches long in that short time. However, most butterfly caterpillars are not considered "pests" because they don't eat enough to damage or kill the host plant.
After reaching full growth, the caterpillar crawls a short distance to a nearby branch or other surface to attach itself, shed its skin, and form a hardened outer shell known as a chrysalis. In nine to 14 days, a butterfly emerges, complete with a new straw-like tongue for sipping nectar.
To welcome these new guests to your garden, provide a pesticide-free environment and include plenty of native plants that provide nectar, such as Phlox Carolina L. (Carolina phlox), Gelsemium sempervirens (Carolina jessamine), Coreopsis verticillata (threadleaf coreopsis), and Rhododendron catawbiense (Catawba rhododendron).
You'll also want to offer protected areas for perching, locations for hibernating, sunny areas for basking and opportunities for puddling, an activity that involves shallow pools of water.
"A lot of gardeners enjoy creating puddling areas," Konradi says. "These are very shallow pools of water where butterflies gather."
A strict nectar diet lacks some important nutrients. By sipping water from muddy puddles, butterflies can get the salts and minerals needed for, among other things, reproduction, she explains.
Sprinkling sand or dirt in the bottom and placing a few small stones as perches will likely entice even more butterflies to congregate, Konradi says.
Also important is having a sunny area for basking. Because butterflies are cold-blooded creatures, they need the warmth of the sun to maintain their body temperature, and some will feed only on plants placed in sunny locations.
An excellent source of information about butterflies and the native plants that support them through all their stages is "Butterflies in Your Backyard," provided through the N.C. Cooperative Extension Service. This font of butterfly information can be found online at http://nando.com/gw.