This and other species of Asclepias are called milkweeds because of their milky sap, which is highly toxic to most organisms, and provides natural defenses to both the plant and the monarch caterpillars which consume it.
Yes, another milkweed! You just can't have too many. Common Milkweed is another native herbaceous perennial that not only adds beauty to gardens but - like Butterfly Weed - also plays a crucial role in supporting pollinators, particularly monarch butterflies. This and other species of Asclepias are called milkweeds because of their milky sap, which is highly toxic to most organisms, and provides natural defenses to both the plant and the monarch caterpillars which consume it.