In its first year, poison hemlock appears as a low-growing cluster of delicate, fernlike leaves. By the second year, it grows a hollow stalk with purple spots that can reach 5 to 10 feet in height. The plant blooms in late spring or early summer, producing flat clusters of small white flowers that resemble Queen Anne’s lace. It is a member of the carrot family and has a deep taproot similar to a carrot.