Rayless Sunflower

Helianthus radula

Native to:
United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Asteraceae
Genus:
Helianthus
Species:
Helianthus radula
USDA Symbol:
HERA

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb
Height:
100 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
jun,jul,aug,sep,oct
Bloom Colors:
yellow

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, birds
Deer Resistant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Native to fire-maintained longleaf pine savannas and sandhills; resprouts from rootstock after fire.

Soil Requirements

Soil Type:
sandy, acidic, nutrient-poor soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
native to dry, open habitats like pine flatwoods

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
7–21 days
Notes:
Seeds germinate readily after cold stratification. Light may improve germination rates.

The above propagation data sourced from Claude AI