Installing a butterfly garden is a quick way to add color, life, and beauty to your property. To do this, choose plants that are essential for these beautiful creatures in different stages of life. Read on to learn what plants to include in your butterfly garden, and one to avoid!
What is a Host Plant?
A host plant is a plant on which an organism lives. In nature, some organisms are generalists and some are specialists. Generalists may survive under a variety of conditions and eat a variety of foods, whereas specialists survive under very specific, often hostile conditions, or eat specific and often toxic foods. A specialist insect may rely on one type of plant for food, so for the insect to be present, the host plant must be in the area. In each section below, explore a butterfly species, a picture of its larva or caterpillar, and its host plant.
Milkweeds for Monarchs
Many people know the link between monarch butterflies and milkweed plants. Monarch caterpillars have evolved to tolerate the toxins, called cardenolides, that milkweeds produce. This gives them an evolutionary advantage because most other caterpillars cannot eat this plant, allowing them to graze without competition. The mutation that causes this tolerance, however, results in the monarch’s dependence on milkweed plants for food. They simply cannot eat anything else. So if you want Monarchs in your butterfly garden, you need milkweed plants to feed their caterpillars.
Whether you have a wet location or a dry one, there is a milkweed plant for your sunny butterfly garden. Butterfly milkweed (Asclepias tuberosa) is a beautiful, orange wildflower, about 18″-30″ tall that likes dry, and even rocky conditions. Swamp milkweed (A. incarnata) is taller, at 36″-48″, and blooms pink. As its name implies, swamp milkweed can grow in wet soils. Both plants can also take average garden conditions and are deer tolerant.
Dutchman’s Pipe for Pipevine Swallowtail
To attract Pipevine Swallowtail Butterflies, plant Dutchman’s Pipe (Aristolochia sp.). Identify the Pipevine Swallowtail butterfly by the row of white spots on its blue or blue-green hind wings. Like the Monarch, it is toxic to birds because of the food it eats: in this case the Dutchman’s Pipe. Because of this toxicity, other butterflies mimic the Pipevine Swallowtail as a defense mechanism.
Dutchman’s Pipe Vine
The Dutchman’s Pipe, or Pipevine (Aristolochia sp.) is a 20′-30′ long vine with large, heart-shaped leaves that form a dense screen. Grow it in average to moist garden soil in full sun or part shade. Because it grows so densely, it was traditionally used to cover porches and arbors to provide shade. Pipevine has interesting, pipe-shaped flowers that are usually obscured by the leaves. All parts of this plant contain aristolochic acid, which is toxic if swallowed.
Spicebush and Sassafras for Spicebush Swallowtail
Very similar to the pipevine swallowtail, the Spicebush Swallowtail is a large, black butterfly with blue and white markings. Differentiate it from the Pipevine Swallowtail by noticing the Spicebush Butterfly’s larger white dots on both the forewings and hindwings and the orange marking at the base of the hindwings. Spicebush Swallowtail caterpillars feed on both Spicebush and Sassafras, two aromatic plants in the Laurel Family (Lauraceae).
The Spicebush Swallowtail caterpillar is marked with false eyes, so it resembles a snake. To protect itself from predators, it also wraps itself in a leaf of its host plant.
An unassuming plant most of the year, spicebush (Lindera benzoin) is a great addition to your butterfly garden. This 10′ shrub blooms in early spring with tiny clusters of yellow flowers, which are followed by small red fruit. During the summer, its green leaves provide a great backdrop to lower flowering plants. In the fall, spicebush leaves turns a clear yellow. Leaves, twigs, and berries are lemon-scented, which makes the plant reliably deer resistant. Spicebush grows in most garden conditions.
Sasafras (Sassafras albidum) is a small tree that is another great addition to your butterfly garden. It is unusual in that it can have leaves of different shapes on the same plant. Some leaves may have three lobes, some may have two, and others may have one. The two-lobed leaves may look like either right-handed mittens or left-handed mittens. Like spicebush, sassafras is aromatic, deer resistant, and does best in full sun to part shade in well drained soil. It offers great fall colors in red, orange, and yellow. Sassafras roots were once used as the flavoring in root beer, and the crushed leaves make the “filé” in filé gumbo.
Pawpaw for Zebra Swallowtail
Like its name suggests, the Zebra Swallowtail butterfly is easily identified by its black and white stripes and long tail. It is normally found from the Mid-Atlantic region to the southeastern United States, and is infrequent farther north. Look for Zebra Swallowtails in low, moist woods where pawpaw trees are found.
The pawpaw tree (Asimina triloba) is the tree from the traditional folk song “The Pawpaw Patch.” This small understory tree produces oblong fruit that tastes like a cross between a banana and a pear. Opossums, racoons, and other animals eat the fruit. Pawpaws flower in April, with inconspicuous brown flowers followed by large drooping leaves that turn a clear yellow in fall, giving the tree a tropical appearance. Pawpaw trees normally grow in moist, rich woods and are tolerant of deer and black walnut.
White Turtlehead for Baltimore Checkerspot
Like the Baltimore Oriole, this striking butterfly shares the colors of black, orange, and white. Its population is spotty throughout the eastern United States in wet meadows and marshes where white turtlehead grows. The caterpillar has similar coloration and once it hatches, it may move onto other plants to feed.
White Turtlehead (Chelone glabra) is a native perennial that grows 2′-3′ tall in moist to wet soils in full sun or part shade. It has an interesting, hooded flower in white to shades of pink that resembles the head of a turtle. White turtlehead blooms in late summer and is deer resistant. For entertainment, watch bumble bees crawl inside the flowers while foraging for food.
The Wrong Plant for your Butterfly Garden
It is a common misconception that Butterfly Bush (Buddleia sp.) is a good choice for your butterfly garden; however, it is listed as an invasive species both in the Mid-Atlantic and on the West Coast. An invasive plant is one that spreads quickly and disrupts natural ecosystems, so the US Forest Service and the Pennsylvania Department of Natural Resources have produced fliers to manage its spread. Additionally, Butterfly Bush attracts adult butterflies, but does not host any native butterfly species. Please do not plant butterfly bush in your butterfly garden!
A great way to learn more about plants for your butterfly garden is through the book, Caterpillars of Eastern North America by David L. Wagner. It includes information on almost 700 caterpillars with photographs and descriptions of both the caterpillar and the butterfly. Under each caterpillar description, look up the Common Foodplants section, which lists the caterpillar host plants. The book also includes a Foodplant Index, which refers you to caterpillars that you may find on a plant. Use these tools to look up a butterfly and see what its caterpillar eats, or look up a plant, and see what butterflies it will attract!
Attracting butterflies is a great way to bring life and beauty to your property. Include some of these host plants and add other native trees, shrubs, and perennials, and watch your yard come alive. And as always, if you need help with landscape design, installation, or garden maintenance, contact us.