Eastern North America
Medium sized shrub growing up to 3 feet tall, with copious orange and yellow flowers and simple, alternate leaves.
Monarch butterflies lay their eggs exclusively on milkweed plants, no other plant serves as a nursery for their babies. When the caterpillars hatch, they eat the semi-toxic leaves, and thereby become less desirable prey to other species.
In return for providing such a protective environment at a vulnerable age, the monarch butterflies continually visit the plant for nectar and pollination. With their extensive travels (annual migration can be up to 3000 miles) the butterflies spread milkweed pollen over a vast area and promote the genetic diversity of this plant.