Hypericum grandifolium is a shrub that is not native to California.
There is a high risk of this plant becoming invasive in California according to Cal-IPC.
[Cal-IPC] Madeira & Canary Islands native: Hypericum grandifolium (large-leaved Hypericum) is a shrub (family Clusiaceae) with yellow flowers and oval-shaped leaves found in the San Francisco Bay area in California. It is native to Madeira and the Canary Islands. It grows in woodlands. It spreads via rhizomes and seeds. Its seeds are buoyant and can be carried by water. (link added by Mary Ann Machi)
Calflora:
Information on California plants for education, research and conservation,
with data contributed by
public and private institutions and individuals.
[web application]. 2025.The Calflora Database
[a non-profit organization].Available:
https://www.calflora.org/(Accessed: 03/28/2025).