Celandine poppies can be found throughout the U.S. and are native to Missouri. To continue enjoying this beautiful flower, we need to protect the woodlands that is their natural habitat. The deciduous poppy grows about 1.5 feet tall. Flowers are yellow with attractive reproductive structures protruding from the center. Flowers produce green seed capsules. Celandine poppies have sap that was used by native Americans for yellow dye.