Knotweed

Polygonum oxyspermum

Native to:
Baltic States, Denmark, Finland, Germany, Norway, Poland, Sweden

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Polygonaceae
Genus:
Polygonum
Species:
Polygonum oxyspermum
USDA Symbol:
POOX2

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb
Height:
50 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
jun,jul,aug,sep
Bloom Colors:
white, pink
Ground Cover:
Yes

Garden & Ecology Notes

Wildlife Value:
birds
Salt Tolerant:
Yes

Soil Requirements

Soil Type:
sandy, nutrient-poor, well-drained soil
pH:
6.0 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
commonly found in coastal areas

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days

The above propagation data sourced from Claude AI