Polygonum Davisiae, or more commonly know as Davis' Knotweed, is a subshrub forb/herb with green foliage and purple flowers of the genus Polygonum. It has a moderate growth rate and a height of 1.3 feet at maturity. Its duration is perennial which means it will grow year after year. It's active growth period is spring and summer, blooms during early summer, is somewhat tolerant of shade and is routinely available commercially. Polygonum Davisiae or Davis' Knotweed's floral region is North America US Lower 48, specifically in the states of California, Idaho, Oregon and Washington.
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