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Lesser Knotweed, Polygonum campanulatum
Persicaria campanulata (Lesser Knotweed). This is a semi-evergreen or herbaceous perennial with veined, dark green, ovate leaves with white-to brownish undersides and short panicles of small, bell-shaped, pale pink flowers.
Tolerates poorly drained areas.
Grown for attractive foliage and flowers and suitable for bog gardens, moist borders and, shady areas by streams or ponds.