Kalm's St. John's Wort

Hypericum kalmianum

Blooms: mid May - mid September

Kalm's Saint John's Wort is endangered in the state of Illinois. Although it is quite rare, small amounts have been spotted in most counties of Illinois. This species of Saint John's Wort tends to grow in woodlands and along river or lake banks. It can grow up to 3 feet in height, with slender leaves and clusters of yellow flowers at the end of the stem.