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Silphium Species, Roughstem Rosinweed, Showy Rosinweed

Silphiumradula

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Family

Asteraceae (ass-ter-AY-see-ee)

Info

Genus

Silphium (SIL-phee-um)

Info

Species

radula (RAD-yoo-luh)

Info

Synonym

Silphium asperrimum

Silphium dentatum var. gatesii

Silphium gatesii

Sun Exposure

Full Sun

Foliage

Unknown - Tell us

Height

36-48 in. (90-120 cm)

Spacing

24-36 in. (60-90 cm)

Hardiness

USDA Zone 3a: to -39.9 °C (-40 °F)

USDA Zone 3b: to -37.2 °C (-35 °F)

USDA Zone 4a: to -34.4 °C (-30 °F)

USDA Zone 4b: to -31.6 °C (-25 °F)

USDA Zone 5a: to -28.8 °C (-20 °F)

USDA Zone 5b: to -26.1 °C (-15 °F)

USDA Zone 6a: to -23.3 °C (-10 °F)

USDA Zone 6b: to -20.5 °C (-5 °F)

USDA Zone 7a: to -17.7 °C (0 °F)

USDA Zone 7b: to -14.9 °C (5 °F)

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)

Danger

Unknown - Tell us

Bloom Color

Bright Yellow

Bloom Time

Mid Summer

Late Summer/Early Fall

Other Details

Gardener's Notes:

Post Comment

positive

neutral

negative

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Silphium Species, Roughstem Rosinweed, Showy Rosinweed

Silphiumradula

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