Description from Possibility Place: A shrub of the wetland and flood plains, Amorpha fruticosa also does well in good garden soil with full sun. Unique flowers are spikes 3-6 inches long that are purple-blue in color and spectacular when blooming in June. Tends to be irregular in shape, and it can get leggy if not cut to the ground every third or fourth year. Indigo Bush is a nitrogen fixer, which makes it a helpful addition to sites that have nutrient poor soils.
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