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Helianthus Species, Rayless Sunflower, Stiff Sunflower

Helianthus radula

Family: Asteraceae (ass-ter-AY-see-ee) (Info)
Genus: Helianthus (hee-lee-AN-thus) (Info)
Species: radula (RAD-yoo-luh) (Info)
Synonym:Centrocarpha radula
Synonym:Rudbeckia radula

Category:

Tropicals and Tender Perennials

Foliage Color:

Blue-Green

Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Water Requirements:

Requires consistently moist soil; do not let dry out between waterings

Where to Grow:

Unknown - Tell us

Height:

24-36 in. (60-90 cm)

Spacing:

12-15 in. (30-38 cm)

Hardiness:

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

Sun Exposure:

Sun to Partial Shade

Light Shade

Danger:

Unknown - Tell us

Bloom Color:

Maroon (Purple-Brown)

Bloom Time:

Mid Summer

Late Summer/Early Fall

Mid Fall

Foliage:

Unknown - Tell us

Other details:

Unknown - Tell us

Soil pH requirements:

Unknown - Tell us

Patent Information:

Non-patented

Propagation Methods:

From seed; direct sow after last frost

Seed Collecting:

Collect seedhead/pod when flowers fade; allow to dry

Allow pods to dry on plant; break open to collect seeds

Allow seedheads to dry on plants; remove and collect seeds

Properly cleaned, seed can be successfully stored

Regional

This plant has been said to grow in the following regions:

Brooker, Florida

Clermont, Florida

Fort Lauderdale, Florida

Gardeners' Notes:

No details have been posted.

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