Southwestern Annual Saltmarsh Aster

Symphyotrichum expansum

Native to:
Belize, Costa Rica, Cuba, Dominican Republic, Ecuador, Guam, Guatemala, Haiti, Honduras, Mexico, Nicaragua, Puerto Rico, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Asteraceae
Genus:
Symphyotrichum
Species:
Symphyotrichum expansum
USDA Symbol:
SYEX

Growth Characteristics

Life Cycle:
Annual | Biennial
Growth Habit:
Forb/herb
Height:
100 cm
Light Requirements:
Full Sun
Drought Tolerance:
Low
Bloom Months:
aug,sep,oct
Bloom Colors:
pink, lavender, white

Wildlife Benefits

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

Keystone Species Ranking

Caterpillar Keystone:
★★★★☆ Butterfly & moth species supported by this genus (NWF)
Pollen Specialist Bee Keystone:
★★★★☆ Native pollen specialist bee species supported by this genus (NWF)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies

Soil Requirements

Soil Type:
moist, nutrient-rich, well-drained soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
tolerates poor drainage
Moisture:
consistently moist
Notes:
commonly found in wet meadows and marshes

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days
Notes:
Seeds germinate best after cold stratification; surface sow on moist soil and keep at 20°C.