Giant hogweed is very tall. Plants typically grow to 10 to 12 feet tall, or more. Leaves can be up to four feet wide, with heavily-toothed edges and deep lobes. Plants tend to have a very large central seedhead (18-24 inches across), with several smaller seedheads in orbit around it. The hollow stem is covered with dark purple blotches, especially near the base, each with its own tiny hair.

hogweed central seed head

leaves with jagged edges

blotches and hairs on stems