Whorled Milkweed (Asclepias verticillata)
Whorled milkweed is a perennial wildflower native to much of North America, including Wisconsin’s prairies, savannas, and open woodlands. Typically reaching heights of one to three feet, it features slender, upright stems lined with narrow, linear leaves arranged in whorls. Each leaf measures about two to three inches long and less than a quarter-inch wide, giving the plant a fine-textured, almost grassy appearance.
From June through September, whorled milkweed produces fragrant clusters of small, white, star-shaped flowers—each about a quarter-inch across. These blooms are highly attractive to a wide range of pollinators, including native bees, butterflies, and even hummingbirds. As a host plant for monarch butterfly larvae, it plays a vital role in supporting their life cycle, offering foliage for caterpillars and nectar for adults.
Adaptable and tough, whorled milkweed thrives in full sun to partial shade and tolerates dry to medium moisture conditions. It grows well in loam, sandy loam, silt, clay loam, and rocky soils, making it an excellent candidate for restoration projects, meadows, and naturalized plantings. Its rhizomatous roots allow it to spread modestly over time, and it readily self-seeds without becoming aggressive.
This species is both deer-resistant and drought-tolerant, and its smooth, narrow seed pods add visual interest in late summer and fall. While its foliage is toxic to livestock and pets, it poses no threat to pollinators and contributes meaningfully to biodiversity. Whorled milkweed is especially valuable in dry prairie restorations, roadside plantings, and pollinator gardens.
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