Credit: David Foley
Cornus nuttallii
Background and story
The Pacific Dogwood (Cornus nuttallii) is a deciduous tree native to the west coast of North America, where it grows in moist, temperate forests from British Columbia to California.
It was first encountered by European botanists in the early 19th century, notably during the expeditions of David Douglas in the 1820s, although he initially mistook it for the eastern species Cornus florida.
The plant was later properly recognised and described as a distinct species by Thomas Nuttall in 1834, with the name formalised by John James Audubon in his honour.
Seeds were introduced to Britain soon afterwards, with early attempts at cultivation recorded in the 1830s, placing it among the many North American trees brought into Irish and British gardens during that period of botanical exchange.
Its large white bracts, often 6–8 rather than the typical four of other dogwoods, quickly made it one of the most admired flowering trees in cultivation.
Did you know?
Its “flowers” aren’t really flowers. The striking white display comes from large petal-like bracts, while the true flowers are tiny and clustered in the centre.
Hardiness and conservation
The recorded RHS hardiness rating is H5, which means this plant is hardy in most places, including many severe winters, provided other site conditions are suitable. The recorded USDA/PFAF hardiness value is 7-9, which is useful as a broad winter-temperature guide, but it should not be read as a direct substitute for the RHS rating. Local hardiness always depends on local shelter, drainage, winter wet, salt-laden wind and the plant’s age and establishment.
The IUCN Red List status recorded here is Least Concern (LC). This means it has been assessed as being at relatively low risk of extinction in the wild.
Additional notes for Ireland and Britain
In Ireland and Britain, Cornus nuttallii is hardy but somewhat demanding, performing best in mild, sheltered gardens with moist, humus-rich, acidic soil. It prefers conditions similar to its native habitat, including light woodland or sheltered sites, and can struggle in exposed or alkaline situations. When well sited, it forms a medium to large tree (often 8–15 metres or more) with a layered structure and striking spring display, occasionally followed by a second, lighter flush of flowers later in the season. However, it has a reputation for being somewhat difficult to establish and is notably susceptible to dogwood anthracnose, a fungal disease that has caused decline in both wild and cultivated populations. In favourable Irish conditions, especially in mild, damp western or woodland gardens, it can still perform very well, but it is generally less reliable than Cornus kousa or hybrids derived from it.
From a conservation perspective, Cornus nuttallii is not globally threatened and is classed as secure across most of its natural range. However, regional populations, particularly in parts of North America, have been affected by introduced fungal disease (anthracnose) and changing environmental conditions, leading to local declines. Despite these pressures, the species remains widespread in the wild and continues to be cultivated, though often supplemented in horticulture by hybrids with improved disease resistance.
Notable features
- It often flowers twice in one year. Unlike most temperate trees, it typically produces a main spring flush and a second, lighter flowering in late summer or autumn.
- It has more “petals” than most dogwoods. Many dogwoods have four bracts, but this species can have six to eight, giving it a fuller, more dramatic appearance.
- It was misidentified when first discovered. The plant explorer David Douglas initially mistook it for Cornus florida and failed to send seeds home, delaying its introduction to cultivation.
- It is highly valued but vulnerable in the wild. Although widespread overall, it has suffered serious regional decline due to dogwood anthracnose, a fungal disease that can kill mature trees.