Current Facts Purple Butterfly sorrel, botanically classified as Oxalis regnelli "Triangularis," is a perennial plant that is a member of the Oxalidaceae, or wood sorrel … Comments: In Illinois, this is the only Oxalis sp. Purple Butterfly sorrel is crisp and acidic with a lemony taste and a slightly sweet undertone. Violet Wood Sorrel … https://nature.mdc.mo.gov/discover-nature/field-guide/violet-wood-sorrel The small pinkish or white colored blooms are an attractive addition to the rich purple … Oxalis, also known as wood sorrel, is a perennial weed that is often mistaken for clover. (Wood Sorrel) that has lavender or pale purple flowers. Other Wood Sorrel species within the state have yellow flowers. It is easily distinguished from clover by the 3 heart-shaped leaflets found on top of each long stalk (or petiole) … This includes Pink-sorrel and similar species with pink flowers and larger leaves, as well as yellow flowered species that are fairly common in flower beds. Seasons/Availability Purple Butterfly sorrel is available year-round. There is a small purple variety called Creeping Wood Sorrel … The false shamrock plant (oxalis triangularis) is a bulb type flowering plant which is also known as the purple shamrock or wood sorrel from the oxalis genus. Both the flowers and leaves open up on sunny days, otherwise they fold up and "go to sleep."