St. John's Wort

Hypericum perforatum

The species name, “perforatum,” comes from the fact that the leaves have translucent dots which appear to be holes when they are put up to the light.  There are about 370 species of Hypericum, but H. perforatum is easy to identify.  Native to Europe and Asia, it has naturalized in N. America, and is considered a “weed” in western range land.  For many years, the USDA had a program to import insects as a form of biological control for this plant.  Good thing it didn’t work, eh?  The common name of the plant is said to originate from the Knights of St. John of Jerusalem, who used it to treat wounds on Crusade battlefields.

Family:  Hypericacae
Life cycle: herbaceous perennial (Zones 3-8)
Native:  Europe, western Asia, and northern Africa, naturalized in N. America, especially western states.
Height: 2-4 feet.
Sun:  Full sun optimal, will tolerate partial shade.
Soil:  Does best on well drained soil, but will tolerate some wet soils. Can be grown with low fertility, but will do better with some compost and/or mulch.
Water:   Has low to moderate water requirement.
Flowers:  Bright yellow flowers, 5 petaled, about ¾ inch across, bloom in mid- to late summer.  Flower petals have small black dots on margins.
Propagation:  Seeds should be stratified for 3 to 4 weeks to improve germination.  Germination occurs in about 2 weeks, and is approximately 70%.  Can sow directly outdoors, or in seedling flats for transplants. Seed is extremely small, so controlling the seeding rate would be difficult outdoors.  Seed  germination is also light dependent, so only cover the seed very lightly.  Transplants are pretty tough to kill.  Plant also spreads via short rhizomes, so larger plants can be propagated via root divisions in the spring or fall of the 2^nd or 3^rd year.  Seed can also be saved from your own plants if some flowers are left to go to seed.  Space plants about 12 inches in the row, with 2 to 3 feet between rows.
Pests:  No major pests observed in our field trials, though the Klamath Beetle (Chrysolina spp.), introduced into California by the USDA in 1944, continues to be a problem for growers west of the Rockies. 
Harvesting:  The flowering tops are clipped when in full flower.  For the absolute best quality, individual blossoms are picked the day they open, but this option would probably only be used if you are making oil or tincture for yourself or your family.  Sold fresh or dried. 
Parts used: Flowering tops, when in peak flower.  Check with buyer as to how much plant material may be included with flowering tops.
Used as:  Infusion, tincture, herb powder, liquid, wash, cream, infused oil.
Medicinal Benefits:   Clinical studies have shown St. John’s Wort preparations to be an effective anti-depressent, sedative, and anti-anxiety treatment.  Oily Hypericum preparations demonstrate an anti-inflammatory action, though no antiviral properties of the herb have been proven.  However, antibacterial effect has been demonstrated, including against penicillin-resistant Staph.  In Europe, St. John’s wort has been approved for use by physicians in treating anxiety, depressive moods, inflammation of the skin, blunt injuries, wound, and burns. The herb can cause increased skin sensitivity to the sun when taken internally.  For many years, manufactured products from St. John’s Wort were standardized to the hypericin content of the herb.  However, it was later found that the efficacy of this herb is due to synergy of several compounds, so now hypericin is simply considered an “indicator” compound, that may or may not actually be linked to how effective the product might be.
Market Potential:  High.  However, much St. John’s Wort now wild crafted in California and other western states.  Can be hand harvested, but some mechanization should be possible.  This herb has received much positive national publicity as an alternative treatment for mild depression.  It also have value for skin healing, and other medicinal uses, so demand for this herb should be good for quite a while.  In Europe, St. John’s Wort is prescribed 20 times more often for depression than Prozac.  Prices range from $4.50 - 25.75 /lb dw for tops with flowers.

KSU Field Trial Data - 2000-2002.  

Summary of field trial data:   Overall, St. John’s Wort seems to be one of the better adapted plants that we evaluated in our plots.  Transplants held up well under transplant stress, and mature plants appear to have few insect or disease pests.  Our results appear to agree with the recommendations of Sturdivant and Blakley (1999), who suggest that 2^nd yr plants yield more than 3^rd year plants.  Our stands also declined in year 3, but this was also confounded with a drought in 2002 at both locations, and fall harvest of these plants, which was not the optimal time of harvest for maximum biomass (which would have been June or July).

If a good price can be obtained for either fresh or dried material, this may be a crop to try in Kansas.  Since buyers are willing to accept some green matter in with the flowers, say 8 - 12 inches, it seems that this crop could be partially mechanized, with a hedge trimmer, if not with a tractor mounted tool.  The tops still need to be dried carefully and cleanly however, or shipped immediately as a fresh product.  A recent e-mail from Europe confirmed that buyers are still looking for this crop.