An easily overlooked plant, whorled milkweed probably occurs in every county in North Dakota. The plant grows in open areas throughout most of the eastern United States.
Whorled milkweed is perennial from a shallow root system.
Plants sometimes are two feet tall, but individuals about half that height are the rule in North Dakota. As in all milkweeds, the flowers are clustered into umbels. In whorled milkweed, about five to ten tiny white flowers form umbels less than an inch across. Fruit is a pod about three inches long and slightly less than a half inch wide. This plant seems to be most common on lightly or moderately grazed prairie.