Milkweed is a type of wild plant with thick stems that ooze a white, milky sap when broken (which is how it got its name). The plant grows clusters of small pink, purple, or orange flowers in summer, followed by interesting seed pods that split open to release seeds attached to silky white threads that float away on the wind.

Milkweed matters tremendously to monarch butterflies. Monarch caterpillars eat only milkweed leaves, and nothing else will do. The plant contains toxins that don't harm the caterpillars but make them taste terrible to birds and other predators. This protection stays with them even after they transform into butterflies. Female monarchs lay their eggs exclusively on milkweed plants, traveling thousands of miles during migration to find them.

Because milkweed often grows in fields and along roadsides, it's sometimes treated as a weed and removed. But many people now plant milkweed in gardens specifically to help monarch populations, which have declined as milkweed has become less common. The plant is also important to many other pollinators like bees and other butterfly species that drink nectar from its flowers.