Erect Knotweed

Polygonum erectum

Native to:
Canada, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Polygonaceae
Genus:
Polygonum
Species:
Polygonum erectum
USDA Symbol:
POER2

Growth Characteristics

Life Cycle:
Annual
Growth Habit:
Forb/herb
Height:
60 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
jun,jul,aug,sep,oct
Bloom Colors:
green, white

Wildlife Benefits

Caterpillars:
★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)

Host Plant for Caterpillars

Nais tiger moth (Apantesis nais)

Garden & Ecology Notes

Wildlife Value:
birds
Salt Tolerant:
Yes

Soil Requirements

Soil Type:
rich, well-drained loamy soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
good drainage preferred
Moisture:
consistently moist
Notes:
prefers floodplain habitats with periodic inundation

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days
Notes:
Seeds germinate readily in spring after cold stratification. Light may improve germination rates.

The above propagation data sourced from Claude AI