Since Fallopia xbohemica is a hybrid, it is not considered to be native to its current distribution in Europe (DAISIE) and North America (FNA). Fallopia ×bohemica is a widespread hybrid between F. japonica and F. sachalinensis. These species are native to Japan, China and Korea, and Japan and the Russian Federation Kurile Island Sakhalin (GRIN, GBIF).
Fallopia ×bohemica is a widespread hybrid between F. japonica and F. sachalinensis. It went unnoticed in the North American flora until recently (P. F. Zika and A. L. Jacobson 2003). It exhibits morphological intermediacy with its parents and is distinguished most reliably by the pubescence along the veins on the abaxial surface of leaves produced early in the growing season. Hairs of F. sachalinensis are multicellular, usually twisted, acute to acuminate at the tip, and 0.2-0.6 mm; those of F. japonica are unicellular, blunt, and barely raised, making the veins appear scabrous. Fallopia ×bohemica has hairs that are unicellular or appearing so (actually often obscurely multicelluar), acute at the tip, and shorter than 0.1 mm. The hairs are easiest to find on fresh leaves; older leaves often are glabrescent and diagnostic hairs are hard to find. Hybrid specimens are most often misidentified as F. japonica (Flora of North America)
Was historically available as an ornamental. In western Washington, the hybrid is more common in cultivation than Polygonum cuspidatum or P. sachalinense. In our field investigations we observed the hybrid had commonly escaped from ornamental plantings, and aggressively colonized riverbanks, roadsides, garden dumps, and disturbed ground (Zika 2003).