Shrubs erect, bushy, 10–50 dm. Stems: internodes 4-lined at first, then terete. Leaves spreading, sessile; blade narrowly elliptic to narrowly elliptic-oblong, 20–70 × 5–15 mm, (proximal usually narrower), base narrowly cuneate to subangustate, margins plane, apex acute to apiculate-obtuse, midrib with 8–12 pairs of branches, tertiary veins densely reticulate toward margins. Inflorescences broadly rounded-pyramidal to broadly cylindric, to 30-flowered. Flowers: sepals lanceolate, unequal, 3–4.5 × 1–2.2 mm; petals bright yellow, not red-tinged, oblanceolate-unguiculate, 12–17 mm; anther gland yellow to orange; styles widely spreading, 8–14 mm. Capsules pyramidal-ovoid to ovoid-ellipsoid, 9–12 × 7–8 mm. Seeds 1.5–2 mm, narrowly winged; testa linear-reticulate to linear-foveolate. 2n = 40.
Phenology: Flowering spring–summer.
Habitat: Disturbed sites
Elevation: 20–500 m
Introduced; Calif., Atlantic Islands (Canary Islands, Madeira).
Hypericum canariense is established at Montecito and Santa Barbara in the hills (P. A. Munz 1974) and along the coast north of Santa Cruz to San Francisco, at locations in Orange and San Mateo counties, and in the San Diego coast region.
The description above agrees with that for Hypericum floribundum regarding sepals lanceolate and acute; in typical H. canariense they are oblong-spatulate and rounded. The variation is continuous; only one species is recognized here.