Tall Evening Primrose is a biennial that sends up 4-6 feet tall reddish stocks topped with bright yellow flowers in its second growth cycle. These stocks emerge from a basal floret of long oblong leaves that are1-3 feet across. Flowers have four heart petals that open in the evening and stay open until late morning. They are a feast for bees, moths, and butterflies. When gone to seed they are a feast for birds. These plants, though somewhat drought tolerant, do well in moist areas of the garden and are usually found at the edges of riparian zones.