Can anyone i.d. this bougainvilla and attest to its hardiness? I found this guy growing at a local campground in z6 in mid-October.
If it is purplish in color it is probably B. spectabilis. None of the Bougainvillea are reliably hardy outside zone 9, although as you can see, they grow fast enough to use as a dieback tender perennial. They have resprouted from the roots on very mature plants that typically lost all top growth at 20F here in the sustained 10 days of freeze we had in most of northern California in December 1990. Smaller dwarf cultivars can be successfully grown as bonsai plants and taken inside for winter. People grow them this way in the Pacific Northwest. Here in the San Francisco Bay Area, you seldom see them as old plants where it regularly freezes each winter, especially if it typically gets below 25F as a normal occurrence. Where it doesn't regularly freeze, this particular species is one of the fastest most rampant growers, and can easily climb 50 feet up into trees/palms, or cover an entire house. This species tends not to hold the colorful bracts as long as some other hybrids. 'Barbara Karst' and 'San Diego Red' are two of the best for extra long bloom here. 'Raspberry Ice' and 'Rosenka' are two good dwarf shrubby types to grow in a container.