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Cornus × horseyi Rehd.

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New article for Trees and Shrubs Online.

Recommended citation
'Cornus × horseyi' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/cornus/cornus-x-horseyi/). Accessed 2026-05-18.

A large shrub, branchlets somewhat four-angled, sparse with appressed trichomes, becoming purple. Leaves deciduous, 5–10(–12) × 2–5.5 cm, chartaceous, elliptic-ovate to oblong-ovate, base cuneate, upper surface yellowish-green, with short appressed trichomes at first, lower surface greyish-green, pubescent with appressed trichomes, five to seven secondary veins on each side of the midvein, margins entire, apex acuminate; petiole 0.5–2 cm long. Inflorescences corymbose, 5.5–6.5 cm diameter, peduncle 3–4 cm long, peduncle and pedicels pubescent; bracts minute, not petal-like. Flowers with petals 0.4–0.5 cm long. Fruits subglobose, 0.6–0.7 cm diameter, dark blue at maturity, with one stone; stone 0.4 cm long, slightly compressed, faintly ribbed. Flowering in spring to summer, fruiting in autumn. (Rehder 1922).

Habitat In cultivation only.

USDA Hardiness Zone 7-8

RHS Hardiness Rating H5

Conservation status Not evaluated (NE)

As described in the entry for Cornus × dunbarii, in abou 1910 a batch of seed from Cornus macrophylla was sown at the Rochester Parks Department, New York, from which two anomalous plants stood out as the seedlings matured (Kehne 1978). These were determined by Alfred Rehder of the Arnold Arboretum to be hybrids of C. macrophylla with C. amomum (which he named C. × horseyi) and C. asperifolia, which became C. × dunbarii: Richard Horsey was then curator and Taxonomist of the Rochester Parks System.

Once again it has remained in deep obscurity, omitted from almost all literature, but remaining in cultivation at the Arnold Arboretum and the Sir Harold Hillier Gardens, where it has formed a big shrub, covered in corymbs of flowers in late July and looking very ornamental (David West, Instagram post 28 July 2022).