The monkeyflower is named for the supposed resemblance of the flower to the face of a smiling monkey, especially if it is squeezed together by your fingers. It is a native perennial herbaceous plant that is a member of the lopseed family.

This species is found in wetland areas throughout most of the eastern and central United States and may have been introduced in limited areas of the West. It is more common in the North than in the South. The monkeyflower grows in wet soils, particularly in swampy areas, wet meadows, pond or stream banks and low woods.

This species is a branching plant that grows one to three feet high and has a square, smooth stem. The flowers have an upper lip with two lobes and a lower lip with three lobes. It generally is a blue-purple color, though examples of pinkish-white are common. The 1-inch long flowers often occur in pairs and rise from the axils of opposite leaves and have a green tubular calyx. Normally the flowers are widely scattered on the plant. A yellow-spotted palate almost totally closes the throat of the flower. Only bumblebees are strong enough to force their way through to obtain nectar. The narrow throat has 4 white stamens and a pistil. The flower has no scent but provides nectar to the bees.

The plant has a taproot and an underground stem called a rhizome. This species can grow 1-3 feet tall. It can spread by means of these rhizomes but is not aggressive. The seeds are small and are contained in a capsule. The leaves are in pairs and have irregular teeth and flaring lobes on each side. It blooms for a long period of time between June and September. It is also called the square-stemmed monkeyflower.