Atlas Cedar ‘Glauca’ · Cedrus atlantica ‘Glauca’

Cedrus atlantica 'Glauca' (Blaue Atlaszeder) is a slow-growing evergreen conifer with dense tufts of silver-blue needles and a strongly pyramidal habit (Habitusform) when young, opening to a broad, flat-topped silhouette with horizontal branching as it matures. Mature height reaches 15 to 20 metres with a spread of 6 to 10 metres over decades; on German sites it follows the same trajectory more slowly than in Iberian cultivation. The blue foliage is the defining character of the Glauca Group within the species, holding colour year-round.

Winter hardiness (Winterhärte) is the central specification question. The species is reliably hardy to approximately minus 18 degrees Celsius on free-draining substrate, with minus 20 degrees Celsius a defensible limit on established trees in sheltered positions. Performance is dependable across the Oberrheingraben (Upper Rhine valley), the Niederrheinische Bucht (Lower Rhine basin), and the milder parts of the Rhein-Main and Stuttgart basins. The species becomes marginal east of the Elbe, in Brandenburg and Saxony, and above 400 metres in the voralpenland (pre-Alpine foothills). The first three winters carry the greatest risk; hardiness consolidates as the tree matures.

Site requirements (Standortansprüche) favour full sun and free-draining loam or sand. The deep taproot (Wurzelverhalten) drives reliable drought tolerance once established but is the source of the species' well-documented transplant difficulty, making mature specimen supply the standard route for project use. The cultivar tolerates calcareous substrates and a wide pH range, including the loess soils of the Rhine corridor. De-icing salt tolerance is low, which removes it from roadside Straßenbaum use under routine German winter salting; it is a Solitärbaum for parks, Stadtwald, campus, and representative landscape settings, outside the GALK-Straßenbaumliste context. Phytophthora root rot appears only on impeded drainage, and heavy wet snow can break the horizontal branches of mature trees.

Maintenance is minimal once established: no formative pruning is required and the cultivar carries none of the genus-level phytosanitary pressure currently affecting Fraxinus or Buxus stock in Germany. Within the climate-adapted species discussion (Klima-Artenmatrix, Zukunftsbaum), Cedrus atlantica 'Glauca' occupies a defined niche: a long-lived, drought-tolerant evergreen structural tree for the milder Klimaregionen, with documented limits beyond them.