New Zealand
Muehlenbeckia complexa is an ornamental plant in the Polygonaceae family, which is native to New Zealand. It is quite vigorous and probably the best species for trimming and topiary. It is semi-deciduous, growing to 15 ft (4.5 m) or more up suitable supports, and produces swollen white berries with black seeds (GBIF).
Sold as an ornamental in California. Listed in Sunset Western Garden Book.