Redwood Database

An index of all Redwood cultivars both in and out of commercial production.

Sequoiadendron giganteum ‘Glaucum’

Giant Redwood

Sequoiadendron giganteum ‘Glaucum’ is a distinctive cultivar known for its glaucous foliage, which has been recognized in cultivation almost since the species was first introduced. Despite this, authoritative dendrological texts, including those by Elwes & Henry (vol. 3, 1908) and various editions of Bean’s work up to the eighth and final edition (Bean 1981), do not discuss this cultivar in detail. Elwes & Henry were aware of its existence through an 1891 work by German dendrologist Ludwig Beissner, but they did not elaborate on it as they had not personally observed the plant.

Although some sources, such as Auders & Spicer (2012), suggest that ‘Glaucum’ has been known since 1860, a German publication from 1865 indicates that it was raised from seed around 1862 at Joseph Baumann’s nursery in Ghent, Belgium (Henkel & Hochstetter 1865). The scarcity of references in key English texts implies that this cultivar either remained limited to mainland European collections or was only planted in Britain to a very limited extent until the early 20th century. Arthur Jacobson noted in 1996 that ‘Glaucum’ had been “very rare in North America until the 1990s” (Jacobson 1996). The largest existing tree in Britain, measuring 37 m in height and 1.15 m in diameter at breast height (dbh) in 2015, was planted in 1926 at Bedgebury National Pinetum, Kent (Tree Register 2024), and is likely one of the earliest plantings of this cultivar in the country. Jacobson also recorded a tree in Tacoma, Washington, USA, measuring 36 m tall with a 1.6 m dbh in 1992, but did not provide a planting date (Jacobson 1996).

‘Glaucum’ is a distinctive plant capable of rapid growth in its youth, but it tends to slow down earlier than the typical species. Two specimens accessioned at the Sir Harold Hillier Gardens, UK, in 1977 measured 21 m × 0.65 m dbh and 24 m × 0.64 m dbh in 2017 (Tree Register 2024). This cultivar is said to be hardier than the species and maintains a more slender form with a smaller trunk and shorter, sparser branches, leading several authors to describe it as gaunt. The young growth is quite intense grey-blue, particularly on young trees, but this characteristic becomes less pronounced as the trees age. The Bedgebury tree, for example, can barely be described as glaucous, but its slender stature and relatively sparse branching are as distinctive as a label.