Scientific Name:
Persicaria maculosa
( syn. Polygonum persicaria )
Pronunciation:
pur-sih-KAIR-ee-uh mak-yoo-LOH-suh
Common Name:
smartweed, lady's thumb
Family Name:
Polygonaceae
Plant Type:
Annual, Invasive plant, Weed (horticultural)
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.
Habit:
Arching, Open, Spreading, Upright
Form:
Irregular, Oval - horizontal
Texture:
Medium
Mature Height:
0.4 - 0.7m
Mature Spread:
0.6 - 1.0m
Growth Rate:
Fast
Origin:
Europe
Hardiness Rating:
Zone 1: (below -46 °C)
Exposure:
Full sun, Part sun/part shade, Filtered shade
Soil/Growing Medium:
Well-drained
Water Use:
Moderate
Landscape Uses:
Erosion control, Fall interest, Fragrance, Group or mass planting, Medicinal plant, Wetland - bogs
Additional Info:
Google. Compare to P. lapathifolia (which lack the dark leaf spot) and confirm ID.
Leaf Morphology:
Form:
Simple
Arrangement:
Alternate
Texture/Venation:
Soft flexible, Heavily veined
Surfaces:
Pubescent
Colour in Fall:
Green, Red
Shapes:
Lanceolate
Apices:
Acuminate, Caudate
Bases:
Cuneate
Margins:
Ciliate
Inflorescence Type:
Spike, Floriferous
Flower Morphology:
Flowers perfect
Number Of Petals:
0
Corolla Shape:
Campanulate
Ovary Position:
Superior
Colour (petals):
Showy, White, Pink
Flower Scent:
Fragrant, Sweet
Flower Time at Peak:
Jul, Aug, Sep
Additional Info:
Five, petal-like sepals
Fruit Type:
Achene
Fruit Colour:
Brown
Fruiting Time:
Oct, Nov
Additional Info:
Not showy,
Bark or Stem Colour:
Green, Red
Organ Modifications:
Runners (or stolons)
Propagation:
Seed, Division - below ground parts
Pest Susceptibility:
(Disease resistant)
