Austrocedrus chilensis (D.Don) Pic.Serm. & Bizzarri

Austrocedrus chilensis was introduced to cultivation from Chile by the British botanist Thomas Bridges in 1847. Bridges is an under-appreciated figure today, but he was a prolific collector in North and South America in the early to mid 19th century. From 1828 onward he spent ‘about 25 years living in Chile at different times, where he collected more than 1500 plants’ (Gardner, Hechenleitner & Hepp 2015). Gardeners might be most familiar with him by virtue of another Chilean plant, the stunning Lobelia bridgesii.

About the time Bridges collected Austrocedrus he appears to have been in a commercial relationship with the nursery firm of Messers Low of Clapton, to whom he dispatched material (Bean 1981). He was not the ‘discoverer’ of Austrocedrus, which was described by David Don in Lambert (1828) ‘from materials found in the herbarium of the Spanish botanists, Ruiz and Pavon, which had been acquired by Mr Lambert’ (Kent 1900). The Low nursery raised ‘a good stock’ of young trees from Bridges’s sending (Gardeners’ Chronicle v. 10, 1850), and the Veitchian collector William Lobb would soon introduce further material, but by the time Elwes and Henry were penning their magnum opus they could report only that ‘by far the greater number of the plants introduced in 1847 were killed, and it is now very rare in cultivation’ (Elwes & Henry 1906–1913).

The very cold winter of 1860–61 seems to have shouldered much of the blame for these losses, but a handful of surviving trees cited by Elwes & Henry hint at greater nuance, such as one at Keir in Perthshire, which at that time was a particularly cold site. W.J. Bean seems to have been alert to this, for he notes that this ‘very pretty small tree […] appears to be quite hardy and grows well but rather slowly’ (Bean 1981). For Elwes and Henry the finest examples known in the early 20th century included trees 14.2 m tall at Whiteway, Devon; 8.5 m at Powerscourt, Wicklow, and 7.6 m at Kilmacurragh, Wicklow (Elwes & Henry 1906–1913). Unfortunately, the few successes that could be reported did little to encourage further experimentation, and damning conclusions in publications like Veitch’s Manual of the Coniferae (Kent 1900) were no doubt influential. Still, further introductions continued to arrive intermittently, including Comber 364, which was planted at Edinburgh in 1926 and which survived until sometime between 2004 and 2008, by when it had attained a height of 12 m and a dbh of 51 cm (Tree Register 2025; pers. obs.).

The tallest ever recorded from British or Irish gardens once grew at Nymans, West Sussex, a property with strong associations with the Comber family and perhaps this tree was also from Comber 364. It was 17 m × 38 cm when last measured by Alan Mitchell in 1977, but has since been lost (Tree Register 2025). The tallest extant tree is also in West Sussex, in Gores Wood at Borde Hill; in 2015 it was 14.5 m × 27 cm. In the grounds of Frogmore in Windsor Home Park a fine tree was 13.7 m × 40 cm in 2021 (Tree Register 2025). Records such as these, and other good trees in excess of 10 m in southeast England at Wisley, Wakehurst and Kew, are not so surprising; more informative, perhaps, are those few good trees away from the increasingly warm and dry southeast. These include a tree 9 m × 32 cm at Hergest Croft, Herefordshire in 2023; 9 m × 26 cm at Pencarrow, Cornwall in 2016; 8 m × 20 cm at the University of Dundee Botanic Garden in 2017 (from a 1980 planting, perhaps traceable to collections made in Argentina in the 1970s by the Danish collector Soren Ødum); and 8 m × 19 cm in Ray Wood at Castle Howard, North Yorkshire in 2021, from a 1990 planting (Tree Register 2025).

In the UK at least most trees planted since c. 1990 owe their presence to the activities of the Royal Botanic Garden Edinburgh’s International Conifer Conservation Programme which has collected Austrocedrus from throughout its Chilean range. Together with veterans like those listed above, the widespread distribution of plants from multiple provenances to a diversity of sites throughout the UK and Ireland has helped to paint a fuller picture of this handsome tree’s requirements in gardens: drainage is key.

Despite Victorian opinion, Austrocedrus is perfectly hardy, but it will generally fail in the wetter and colder regions of Britain unless planted on extremely freely draining soils, ideally in a sheltered sun trap. Plants in suboptimal conditions might appear well enough for a while, but where the soil is too wet plants will soon turn chlorotic and exhibit dieback. This is also a symptom of too much shade, which this tree seems especially to hate in northern gardens (pers. obs.). At Murthly Castle in central Perthshire three young trees are thriving on gravelly, alluvial soils on a raised part of the River Tay floodplain, in an area that might reasonably at one time have been deemed too cold. At Eastnor Castle in Herefordshire another planting, on the edge of a small disused quarry, is establishing beautifully. Even in drier, warmer, eastern areas, good drainage is still important: several young trees planted on sandy soils at the Yorkshire Arboretum and thriving, as are others on shallow soils above solid chalk at Pampisford, Cambridgeshire (pers. obs.). Shelter from cold winds while establishing seems to be important (pers. obs.).

Where it thrives Austrocedrus makes a very handsome evergeen, and is neither too fast growing nor ultimately too large, and yet it is almost unheard of across large parts of central and southern Europe and the south western United States, where warm, dry summers ought to suit it very well. Hardiness is likely an issue in a truly continental climate zone, but in large parts of southern Europe, the Mediterranean basin and southern California, its absence is mystifying. The few examples that exist in these regions are almost entirely confied to specialist collections (pers. obs.). There are a few examples in Belgium, at Kalmthout, Wespelaar, and the pinetum Jean Ickx (Arboretum Wespelaar 2025) but records from elsewhere are very few, and it is hard to discern whether this is due to a lack of demand or lack of supply. Jacobson (1996) notes that it was in North American commerce before 1900 but is ‘rare, and limited to Pacific Coast cultivation’. The only American example he sites is a tree growing in Seattle, 6 m tall after 46 years.

Austrocedrus has been recommended for general planting in parts of Australia (e.g. Rowell 1996) and it was selected as the subject for one of one hundred forest plots to be established in the Australian National Arboretum in Canberra. The trees were planted in ‘forest 57’ in 2011 (Australian National Arboretum 2025). Records from New Zealand are even fewer; Jacobson cites a specimen in Nelson, planted in 1924 and 7.3 m tall × c. 23 cm dbh in 1969 (Jacobson 1996).

‘Flat-leaved’ Cupressaceae like Austrocedrus can be difficult to propagate vegetatively, but some success has been reported. At the Royal Botanic Garden Edinburgh in the mid 20th century ‘cuttings of ripened wood (brown at base) with heel inserted in 75% peat, 25% sand mixture, in mist unit with medium temperature of [18–23°C], rooted 50% successfully’ (Henderson in Fordham 1977). A modern coir-perlite mixture would surely work just as well. Gardner et al. (2006) report that rooting takes two to three months. Austrocedrus is easily raised from seed, but cultivated trees require a long, hot summer if their seed is to ripen (pers. obs.) and wild trees have a short seeding season. A period of cold stratification is beneficial (Gardner et al. 2006).

In recent years wild populations of Austrocedrus have subject to significant and varied pressures. Logging, though less of a problem than it once was, continues in some areas, but historic loss and associated habitat change have reduced the species’s area of occupancy in Chile; in Argentina the North American conifer Pseudotsuga menziesii has become a serious invasive pest of Austrocedrus forests (Thomas 2019). Throughout the range there has been significant decline and increased mortality of Austrocedrus in recent decades, caused by a condition known as ‘mal des ciprés’ (cypress sickness) (Thomas 2019). Imperfectly understood, this is widely considered to involve complex environmental factors interacting with the pathogen Phytopthora austrocedri, a damaging disease affecting a broad range of Cupressaceae. Although this disease was described from Austrocedrus forests in Argentina, it has also been detected in Europe. It is a notifiable disease in the UK where it is responsible for dieback of native Juniperus communis populations, and where it is known to affect a broad range of Cupressaceae genera, both in gardens and the wider landscape (Forest Research 2025).

There are no significant cultivars of Austrocedrus. Those noted below include three that were selected in the 19th century, and one much more recently named cultivar, but in reality none of these differs significantly from the diversity that one typically sees in a batch of seed raised trees. Bean’s account of the species includes a curious note – ‘Comber found a variegated form at St Martin de los Andes in the Argentine, in October 1926’ (Bean 1981) – but no further details have been traced. No such form is mentioned in the authoratative encylopaedia of conifer cultivars prepared by the late duet Aris Auders and Derek Spicer (Auders & Spicer 2012) which suggests nothing came of it.