Hypericum canariense

Photo courtesy Joseph DiTomaso

Synonyms: Hypericum floribundum

Common names: Canary Island St. Johnswort; Grenadillo

Hypericum canariense (Canary Island hypericum) is a rhizomatous perennial shrub (family Clusiaceae) found on the central and south coast of California and in the southern San Francisco Bay region. Canary Island hypericum infests disturbed areas, especially in coastal sage scrub and grassland habitats. This ornamental shrub forms dense stands that exclude native species. It is not yet widespread, but its prolific seed production makes rapid spread possible.

Rating: Moderate

Cal-IPC Resources

  • Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.
  • CalWeedMapper - Statewide maps, climate models, and reports.
  • Cal-IPC News - Our quarterly newsletter. Each issue is available as a pdf.
  • Cal-IPC Symposium Proceedings - Presentations and papers from our annual Symposium.
  • Don't Plant a Pest! - Select your region to find non-invasive alternatives to ornamental species. Also see our statewide brochure on trees.

    Other Resources

    Symposium Presentations

    • Dlugosch, K. (2002). Recently-introduced shrub Hypericum canariense (Canary Island St. Johnswort). California Exotic Pest Plant Council Symposium 2002. Sacramento, CA.
    • Tu, M. and J. M. Randall (2002). 2002 Red alert! New introductions and recent expansions in California. California Exotic Pest Plant Council Symposium 2002. Sacramento, CA.
    • Tu, M. and J. M. Randall (2003). 2003 Cal-IPC red alert! New invasions, recent expansions, and a few others to be on the look-out For. California Invasive Plant Council Symposium 2003. Kings Beach, CA.

    Cal-IPC News Articles

    • Dlugosch, K. (2002). Recently-introduced shrub Hypericum canariense (Canary Island St. Johnswort).
    • Tu, M. (2001). Red alert! Hypericum canariense L. (Canary Island St. Johnswort). CalEPPC News. 9: 6,10.
    • Tu, M. (2002). Hypericum canariense. CalEPPC News. 10: 10.
    • Tu, M. and J. M. Randall (2002). 2002 Red Alert! New introductions and recent expansions in California.
    • Tu, M. and J. M. Randall (2003). 2002 REd Alert! New introductions and recent expansions in California.