St. John’s Wort or St. Peter’s Wort or St. Andrew’s Cross?

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St. Peter’s Wort (Hypericum crux-andreae) is a shrubby native member of the St. Johns wort family with only four petals instead of the usual five. Walking through sandy sites and woodland paths found in the pine barrens of our area you may come across this small upright shrub with brilliant lemon-yellow flowers at its branch tips, glowing against a flaming crimson backdrop of wild blueberry bush leaves. In its native habitat this evergreen shrub is usually found in semi-shade. This is not a plant you come across every day. St. Peter’s wort is critically imperiled in Florida, according to the Institute for Regional Conservation. Its range extends as far north as New York, but according to the U.S. Department of Agriculture, it has disappeared from Pennsylvania, and Kentucky lists it as threatened. It’s a member of the same family as St. John’s wort, and while St. Peter’s-wort looks much like St. Andrew’s cross, (H. hypericoides), with just the four flower petals and their habitats sometimes overlap, St. Andrew’s cross has much narrower petals.
The genus Hypericum contains approximately 500 species found all over the world in temperate to tropical areas. Some species are used for their healing properties in folk medicine. The St. Peter’s Wort member of this group has an interesting past in that regard. Historical records from the early 1900’s note that the Choctaw Native American Indian tribe of Bayou Lacomb, Louisiana used this plant for analgesic purposes and used a decoction of the root for colic.

Several species are used commercially and in the garden as ornamental plants because of their large, spreading flowers. Aaron’s beard, or Creeping St. Image of St. Peters WortJohn’s wort (H. calycinum) is one that we’re familiar with, especially if our landscapes have slopes or sandy soils as this plant has some drought tolerance while providing purplish fall color and starbursts of color in showy yellow flowers with lots of stamens in a ring at the center of the flower.

Be advised, not all Hypericum species are suitable for use around the home. Hypericum perforatum, also know as St. John’s Wort or Klamath Weed is a flowering shrub native to Europe. It gets its name from the fact that it often blooms on the birthday of the biblical John the Baptist and the yellow flower was traditionally gathered for the feast named for this saint. St. John’s wort has been used since the Middle Ages for neuralgia, depression, and various “nervous” conditions. This plant is poisonous at all growth stages can be a problem for our animals. When an animal eats H. perforatum, the poisonous compound in the plant, hypericin, reaches the skin from an internal route (stomach to blood to skin). Here it sensitizes the skin to sunlight and causes lesions; only white or unpigmented areas are affected.

Now that the weather is cool and dry, it’s the perfect time to get out and locate photo worthy native plant species near you. Our own San-Lee Park on Pumping Station Road here in Sanford is a great place to see some real treasures. Also, NC can boast of dozens of state parks, recreation, and natural areas, as well as many local community trails to investigate. Find a park near you.

Minda Daughtry is Horticulture Agent with North Carolina Cooperative Extension in Lee County.