Florida is home to 34 species of hypericums, yellow wildflowers with many stamens and 4 or 5 petals. Their confused and confusing common names often honor saints. St. Johns-wort (Hypericum perforatum) is widely sold as an herbal medicine to treat mild depression.
Many moons ago, all of the 4-petaled plants belonged to the genus Ascryum, but now they all belong to the genus Hypericum. Species matters!
They bloom more or less throughout the year. Some species occur in moist habitats, and other species are found only is dry scrub settings.
On our visit to the Sebastian Harbor Preserve, we saw (at least) 3 different species of Hypericum …
Roundpod St. John’s-wort (Hypericum cistifolium)
Also called cluster-leaf St. John’s-wort, this plant grows in moist, damp areas. It can grow to be up to 3′ tall. Its opposite leathery leaves are linear to elliptical, sessile (stalkless), and widest near the base.
Four-petal St. John’s-wort (Hypericum tetrapetalum)
Also called heart-leaved St. Peter’s-wort, this plant has distinctive clasping greyish-green leaves that are wider at the base. With age its stems become reddish and woody. Its bright yellow, 4-petaled flowers are solitary. You usually will find their plant growing in low wet pinewoods.
Sandweed (Hypericum fasciulatum)
Also known as peelbark St. John’s-wort, this plant prefers low wet places, and you often will find great bands of this plant growing on the edges of ponds. Its stalkless opposite leaves are somewhat clustered in the leaf axils, and its margins (edges) roll under.
These three species are not found at the Oslo Riverfront Conservation Area (ORCA)., but St. Andrew’s cross (Hypericum hypericoides) is. Its opposite, stalkless leaves are somewhat wider the tip. Its 4-petaled yellow flowers are solitary and terminal. You will find this plant growing in the sandy soil of upland hammocks and pinelands. It grows along the loop trail at north ORCA where the scrubby pine flatwoods are transitioning to upland hammock.
Habitat matters to ID!