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.Cal-IPC Rating: Moderate — Alert?
CDFA Rating: B*?
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.
Species ID Card
Invasive Species ID Card - To support field identification of early detection species, Cal-IPC has designed a set of Species ID cards that can be downloaded, printed double-sided, and trimmed to size.
Weed Management Notes
- Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.
Cal-IPC Newsletter Articles
- Weed biological control agents approved for California. Pitcairn, Michael J.; Smith, Lincoln; Moran, Patrick. Vol 22, Issue 1
- Wildland Weed News. editor. Vol 17, Issue 2
- Hypericum canariense. Tu, Mandy. Vol 10, Issue 4
- Red alert! Hypericum canariense L. (Canary Island St. Johnswort). Tu, Mandy. Vol 09, Issue 3
Cal-IPC Symposium Presentations
Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.
- Successes, failures, and lessons from the Orange County CNPS Emergent Invasive Program. Vanderhoff, Ron (2019)
- 2002 Red alert! New introductions and recent expansions in California. Tu, Mandy; Randall, John M. (2002)
Other Hypericum canariense Information
- Bugwood - National database from the Center for Invasive Species and Ecosystem Health at the University of Georgia.
- CalPhotos - Images of plants taken mostly in California.
- Calflora - Distribution map and records of this species in California.
- CalWeedMapper - Distribution map of this species in California with ability to determine regional priorities.
- EDDMapS - Distribution of this species in North America.
- Jepson Interchange - Information on this plant's taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
- USDA PLANTS Database - Information on identification and distribution, with links to websites in individual states.