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Ministry of Agriculture, Food and Rural Affairs


Other Common Names Include: Warriors wound, amber, goatweed, touch and heal, hundred holes, terrestrial sun, grace of God and herb of St. John

Latin Name: Hypericum perforatum

Plant Family: Hypericaceae (Guttiferae

Close Relatives: No close commercial or weedy relatives in Ontario

Uses and Markets: Medicinal; natural health product (e.g. depression, nervous system disorders, etc.)

Vegetative growth of St. John’s wortSt. John’s wort in bloom
Production Life Cycle in Ontario


Hardiness Zone


Special Notes

The temperature during germination must be lower than 20°C (optimally 15°C), otherwise germination is inhibited.

Propagation method

Most commonly by transplants from seeds, less commonly by direct seeding, division (spring or autumn), cuttings.

Greenhouse Seeding/Propagation Dates

Late winter

Field Seeding Date:


Field Transplanting Dates

Spring, 8-10 weeks after seeding.

In-row spacing

15-30 cm

Between row spacing

40-75 cm

Optimal Soil temperature at planting



No current Ontario fertility recommendations exist. Research and recommendations from outside Ontario do not necessarily apply to Ontario growing conditions. In Saskatchewan, research has shown minimal effects of nitrogen on fresh and dry herb yields. Research from Iran and Chile has shown an increase in yield up to 250 kg/ha N, but medicinal quality may be reduced at these rates. Click here for phosphorus and potassium application guidelines and for more information on specialty crop fertility.

Soil type

Well-drained soils; sandy soils.

Soil pH

Acidic to alkaline soils.

Special requirements for growth habit


Optimal Temperature Range

Temperate climate

Temperature sensitivity

Frost sensitive (young tissues only).

Irrigation requirements

Irrigation is beneficial under normal Ontario conditions.

Days to harvest

Early summer starting in year 2, harvest at 50% bud and 50% flower stage.

Specialized equipment

Forage harvester.


Flowering tops (top 20 cm optimal).

Harvest Scheduling

1-2 annual harvests

Hand harvest or machine harvest

Hand harvest or machine harvest

Quality parameters/grades

No established grades. Quality is determined by the market.  Sold fresh or dried.

Additional Harvest Notes

Harvest in morning when oil content is highest.

Post harvest
Special handling/curing

Handle carefully to avoid bruising.

Storage Conditions

Relative humidity (RH): Low humidity after drying, high humidity for fresh.

Drying Temperature: 30-40°C

Temperature: 4°C   

Air Exchange: N/A

Duration: 7 months after drying

Specific pests observed on this crop in Ontario (observations based on limited experience with this crop)

Insects and Invertebrates: St. John’s wort beetle (Chrysolina spp.);

Diseases: Anthracnose (Colletotrichum gloeosporioides), fungal crown and root rots (e.g. Fusarium)

Other Potential Pests: The following pests have not been observed on this crop in Ontario. However, they are either significant concerns for closely related plants in Ontario, or are reported on this crop in other production areas. This is not a comprehensive list of all potential pests. Not all of these pests will necessarily survive Ontario’s climate, but could potentially survive in a protected environment (e.g. greenhouse, storage facility)

None reported.  Scout crop regularly for potential pests.


Commercial production in Ontario is often not possible due to the combined effects of St. John’s wort beetle and anthracnose.  In Ontario, Chrysolina beetles are sometimes less severe on heavier soils, but this is less optimal for crop growth. Click here for more information on these pests. This crop is not in a crop group. There are few to no pest control products registered on this crop in Ontario.

Chrysolina beetle on St. John’s wort Chrysolina beetle larva on St. John’s wort Anthracnose on St. John’s wortEffect of Chrysolina beetles and anthracnose on St. John’s wort
Additional Notes

Research has been conducted at the University of Guelph to establish micropropagation procedures for this crop.

Ontario Research Projects Used to Create This Profile
  1. McKeown, A.W., C.J. Bakker and J. Schooley. 1998-2002. Herb Demonstration Garden, University of Guelph Simcoe Research Station, unpublished.
  2. Murch, S.J. and P.K. Saxena 2006. A melatonin-rich germplasm line of St John's wort (Hypericum perforatum L.). J. Pineal Research 41: 284–287.
  3. Murch, S.J. and P.K. Saxena 2006. St. John’s wort (Hypericum perforatum L.): Challenges and strategies for production of chemically-consistent plants. Canadian Journal of Plant Science 86: 765–771.
  4. Westerveld, S., Elford, E., Filotas, M. and J. Todd. 2010-present. OMAFRA herb demonstration garden. OMAFRA Simcoe Resource Centre, unpublished.
  1. AFIF report, 2000-2001. Herb & Spice. In Specialized Crop Production "Spoke Program", Agri-Food Innovation Fund Annual Technical Report 2000-2001 (pg 36-44). Regina, Government of Saskatchewan.
  2. Azizi, M. and T. Omid-Beigi. 2001. Effects of different levels of nitrogen and phosphorus fertilizer on growth, yield and hypericin content of St. John’s wort. Iranian Journal  of Agricultural Science 32: 720-725.
  3. Berti, M., Hevia, F., Wilkens, R., Joublan, J.P., Serri, H. and J. Allende. 2000. Nitrogen fertilization in St. John’s wort (Hypericum perforatum L.) in Chillan, Chile. Ciencia  e Investigacion Agraria 27: 107-115.
  4. Cuthbertson, Y. 2006. Success with Herbs. Guild of Master Craftsman Publications Ltd., East Sussex UK.
  5. Foster, S. and J.A. Duke. 2000. Eastern/Central Medicinal Plants and Herbs. Houghton Mifflin Company, New York.
  6. Gardiner, A. 1995. Fifty Useful Herbs. Promotional Reprint Company Ltd., London ON.
  7. Government of Saskatchewan.  2009. St. John’s Wort.
  8. Hartung, T. 2000. Growing 101 Herbs that Heal: gardening techniques, recipes and remedies. Storey Publishing, North Adams MA.
  9. Kowalchik, C. and W.H. Hylton. 1998. Rodale’s Illustrated Encyclopedia of Herbs. Rodale Press, Emmaus PA
  10. McVicar, J. 1994. Jekka’s Complete Herb Book. Raincoast Books, Vancouver.
  11. Sturdivant, L.  and T. Blakley . 1999. Medicinal Herbs in the Garden, Field & Marketplace. San Juan Naturals, Friday Harbor WA.