Hypericum ascyron (considered by many to be synonymous with Hypericum pyramidatum) is native to streambanks and moist wooded slopes from Maine to Manitoba south to Maryland, Indiana and Kansas. Great or also known as Giant St. Johns Wort has large attractive ... flowers and foliage. Although, the blooming period is relatively short. Giant St. John’s Wort is easy to identify because of its large size and the presence of 5 styles on its flowers and seed capsules. Other large Hypericum spp. are usually woody, rather than herbaceous, and they usually have only 1-3 styles.