Shasta Knotweed

Polygonum shastense

Native to:
United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Polygonaceae
Genus:
Polygonum
Species:
Polygonum shastense
USDA Symbol:
POSH

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Shrub , Subshrub
Height:
30 cm
Light Requirements:
Full Sun
Drought Tolerance:
High
Bloom Months:
jun,jul,aug,sep
Bloom Colors:
white, pink
Ground Cover:
Yes

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies
Deer Resistant:
Yes

Soil Requirements

Soil Type:
rocky, well-drained, nutrient-poor soil
pH:
5.5 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
native to mountainous regions with sparse vegetation

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days
Notes:
Seeds benefit from cold stratification for 30-60 days to break dormancy.

Pre-treatment: Seeds are placed into fine mesh bags and soaked in a 1% hydrogen peroxide (3:1 water/3% hydrogen peroxide) for 24 hours, then rinsed and placed in water for an additional 24 hours. Seeds are layered in peat and placed into cold stratification (33.8 to 37.4 °F) for 60 days. Check seeds in peat weekly and treat with 1% hydrogen peroxide if mold is evident.

Source: npn.rngr.net