Scientific Name: Persicaria maculosa ( syn. Polygonum persicaria )
Common Name: smartweed, lady's thumb
Family Name: Polygonaceae
Origin: Europe
Hardiness Zone: Zone 1: (below -46 °C)
Plant Type: Annual, Invasive plant, Weed (horticultural)
Mature Size: 0.4 - 0.7m x 0.6 - 1.0m (height x width)
Habit: Arching, Open, Spreading, Upright
Form: Irregular, Oval - horizontal
Texture: Medium
Landscape Uses: Erosion control, Fall interest, Fragrance, Group or mass planting, Medicinal plant, Wetland - bogs
Exposure: Full sun, Part sun/part shade, Filtered shade
Soil or Media: Well-drained
Leaves: Simple, Alternate, Soft flexible, Heavily veined, Pubescent, Lanceolate, Ciliate
Flowers: Spike, White, Pink, Jul-Aug-Sep
Fruit: Achene, Brown, Oct-Nov
Key ID Features:
Erect reddish stems with swollen joints; leaves alternate, lanceolate, usually dark spotted, 3-10cm long; stipules fused into a stem-enclosing sheath that is loose and fringed with bristly hairs on top; inflorescence a dense spike, often nodding; achenes 2-3mm long, shiny and almost black.