Sweet Gum ‘Globosa’ · Liquidambar styraciflua ‘Globosa’

Liquidambar styraciflua 'Globosa' is the compact, dome-headed selection of the American sweet gum, reaching three to five metres in both height and spread at maturity. The crown develops as a dense, naturally symmetrical globe that does not require formative pruning to hold its shape. Growth is slow to moderate, which keeps the form proportionate in confined settings and avoids the overscaling typical of the species form.

Winter hardiness extends across USDA zones 5a to 9b, with the species reliably surviving absolute minima around minus 28 °C and tolerating sustained summer maxima above 35 °C where root depth is adequate. Drought tolerance is moderate once established; salt tolerance is low, which restricts coastal use to sheltered situations away from direct sea spray.

Reliable across Atlantic, Continental, and warm-temperate Mediterranean Europe, from coastal Ireland and the Netherlands through the Po valley and into the Pannonian basin. Performance holds in sheltered sites well into central Poland and southern Scandinavia, but extended boreal exposure and high-altitude continental positions sit outside the dependable envelope. Acidic to neutral, freely drained loams give the strongest autumn pigmentation; on calcareous substrates the autumn show is muted and chlorosis can appear.

Star-shaped, deeply lobed leaves emerge a glossy mid-green and turn through yellow, orange, scarlet, and purple over a long autumn window, often holding colour into early winter in milder maritime climates. The grey, fissured bark and persistent spherical fruit capsules carry visual interest through the leafless months. In the European urban canon the cultivar sits in the niche occupied by smaller-stature street selections such as Acer campestre 'Elsrijk' or Pyrus calleryana 'Chanticleer', but brings the sweet gum's distinctive autumn palette to specifications where a full-size Platanus or Tilia would be unmanageable.