A few years ago, my daughter and I were in a public park, hiking up a steep road in the direction of the highest point in our state. Not far from the summit, a large butterfly stopped to rest on the pavement in front of us. The slender “tails” on the lower wings marked it as a member of the swallowtail clan, but it did not look anything like the common tiger swallowtails that frequent our garden’s butterfly bushes. When the butterfly opened its wings, we saw a flash of brilliant, iridescent blue, and I knew that we were looking at a pipevine swallowtail or Battus philenor, a species that I had only seen in books.
The butterfly stayed in one place long enough for us to get a good look. It had a typical swallowtail configuration—two delta-shaped upper wings, and two rounded lower wings that ended in “tails”. White dots outlined both sets of wings. The undersides of the black wings, visible when the insect closed them, were flashed with blue, as was the lower half of its slender body. The flashy white dots on the undersides were complemented by additional orange ones. The overall effect was quite spectacular, and more than justified another of the insect’s common names, “blue swallowtail”.
The “pipevine swallowtail” name derives from the fact that its larval host plant is the deciduous pipevine, or Aristolochia. Several pipevines are native to parts of North and South America. The pipevine swallowtail that we saw was most likely nourished by large-leafed Aristolochia, known botanically as Aristolochia macrophylla, which is native to the eastern United Sates. Its common name is “Dutchman’s pipe”. It is a rather large—15 to 30 feet—vine native to eastern North America. Garden writers often refer to Dutchman’s pipe as “old-fashioned”, because it was beloved by earlier generations of gardeners who used it to ornament porch pillars and backyard trellises. Somewhere along the line, pipevine was left behind in the push for smaller, showier plants. Aristolochia is really due for a renaissance sometime soon, as so many of us are investing in butterfly and pollinator-friendly species.
Dutchman’s pipe is a beautiful woody vine that covers itself with large, overlapping, heart-shaped leaves during the growing season. That leaf density means that it makes a very effective screen for less-than-beautiful features, like chain-link fences. It grows fast in full sun or light shade, and though its optimal dimensions are a little intimidating, the vine can be kept in check by pruning after it has flowered.
And the flowers, which appear in late spring, are what gave rise to the “pipe” nickname. They are among the most unusual in the plant world—each is a curved, light brown, somewhat bulbous tube that flares out into a mouth-like structure made up of three brownish purple lobes. The flowers are shy, often at least partially hidden by the large leaves. At some time in the past, the blooms reminded people of Dutch smoking pipes, and the nickname has stuck.
The flowers and leaves remind pipevine swallowtails of home, because the voracious, somewhat horned caterpillars stuff themselves on the leaves until they enter the chrysalis phase and metamorphose into butterflies. Once they take wing, the swallowtails favor a varied diet, especially thistles, ironweed, phlox, and other plants with pink or purple flowers.
All of that means that if you have a garden, even a fairly small landscape, you can encourage the beautiful pipevine swallowtail. The vine needs vertical space, but a fence, trellis or arbor will take care of that. Plant the favored nectar species at the feet of the vine, and you will have taken care of the butterfly’s needs.
Pipevine swallowtails have the brightest blue wings in this part of the world, though they are not quite as brilliant as those of the famous blue morpho of tropical New World areas. I can only see those in butterfly houses, so I am hoping that when the growing season rolls back around, I can lay hands on a pipevine. The requisite purple and pink flowers are already in the garden.
Pipevines are not easy to find in the average garden center, but you can order one from an online vendor when the spring ordering/shipping season starts. Try Fieldstone Gardens, 55 Quaker Lane, Vassalboro, ME 04989-3816; (207) 923-3836, www. fieldstonegardens.com.