About Whorled Milkweed: Whorled Milkweed has established itself across most of the United States as one of the most common varieties of milkweed. Its foliage is valuable to butterfly larvae, especially monarchs, since it blooms late in the season. Dry fields, rocky slopes, meadows, and prairies all provide a good home for this delicate looking but hardy plant. Its Latin name, “verticillata,” means “whorled” and comes from the arrangement of its grass-like leaves around its stem. In 1753, eminent botanist Carl Linnaeus gave this plant its Latin genus name, Asclepias. Asclepias, the name of the legendary Greek representation of medicine and healing, is especially appropriate since this plant formerly had various medicinal uses. In spite of its highly toxic nature, Whorled Milkweed attracts flocks of butterflies; butterflies are immune to the plant’s poison, and actually become rather poisonous themselves as protection from predators.
Whorled Milkweed Germination: In late fall, direct sow just below the surface in full sun and dry or well drained soil. This plant also grows well in dry, rocky soil or sand. Plant three seeds together every 18-24 inches. Germination will take place in the spring, after the last frost. When the seedlings appear, thin to the strongest plant; seedlings usually do not survive transplanting, since they resent any disturbance of their roots. For spring planting, mix the seeds with moist sand and refrigerate for 30 days before direct sowing.
Growing Whorled Milkweed Seeds: Young plants should be watered until they become established; mature plants can tolerate drought but grow best with occasional watering. This plant spreads rapidly, but volunteer plants can easily be removed if unwanted. It will also self seed. The flowers attract many bees and butterflies. Deer and rabbits avoid this plant. Whorled milkweed is highly toxic to horses and cattle.
Harvesting Whorled Milkweed: This makes a striking cut flower. Cut the stems long, choosing flowers that have just opened. Keep in mind that the milky sap is mildly toxic and can irritate the skin.
Saving Whorled Milkweed Seeds: After the plant finishes flowering, 3-4” narrow pods will form. Be sure to harvest the pods before they split and the silky fluff carries the seeds away on the wind. As soon as the seeds inside the pod ripen to their mature brown color, remove the pods and spread them out to dry. Split open the pods and take out the silky seed material. Remove the fluff from the seeds. Store the seeds in a cool, dry place.
Detailed Whorled Milkweed Info: Origin: US Native Other Common Names: Whorled-leaf Milkweed, Horsetail Milkweed, Eastern Whorled Milkweed Duration: Perennial Bloom Time: Summer Height: 24-36 inches Spacing: 18-24 inches Light: Full Sun to Part Shade Soil Moisture: Medium to Dry USDA Zone: 3a-9b Seeds Per Oz: 10,600 Produces delicate, dense needle-like foliage and 2-3” clusters of scented white flowers.