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Attractive to bees. Self-seeds in moist soil.
Purple loosestrife, Loosestrife
Lythrum genus (Purple loosestrife). These are summer-flowering perennials that thrive by the waterside and in bog gardens. They will produce showy spikes of pink-purple flowers.
They will grow in most soil conditions as long as there is moisture. Grow them in full sun or semi-shade.