Oenothera Flava, or more commonly know as Yellow Evening Primrose, is a forb/herb (a forb/herb is a non-woody plant that is not a grass) with green foliage and yellow flowers of the genus Oenothera. It has a moderate growth rate and a height of 2.5 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 mid spring, is somewhat tolerant of shade and is routinely available commercially. Oenothera Flava or Yellow Evening Primrose's floral region is North America US Lower 48, specifically in the states of Arizona, California, Colorado, Idaho, Montana, North Dakota, Nebraska, New Mexico, Nevada, Oregon, South Dakota, Texas, Utah, Washington and Wyoming.
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