Taxonomy

Division:

Magnoliophyta | - Flowering plants

Family:

Asteraceae

Genus:

Silphium

Species:

Silphium simpsonii

USDA Symbol:

SISI

Growth Characteristics

Life Cycle:

Perennial

Growth Habit:

Forb/herb

Height:

150 cm

Light Requirements:

Full Sun,Part Shade

Drought Tolerance:

High

Bloom Months:

jul,aug,sep

Bloom Colors:

yellow

Wildlife Benefits

Butterflies & Moths:

★☆☆☆☆ Documented Lepidoptera association (GBIF)

Keystone Species Ranking

Pollen Specialist Bee Keystone:

★★☆☆☆ Native pollen specialist bee species supported by this genus (NWF)

Garden & Ecology Notes

Wildlife Value:

birds, butterflies

Deer Resistant:

Yes

Soil Requirements

Soil Type:

rich, well-drained loamy soil

pH:

5.5 - 7.0 (slightly acidic to neutral)

Drainage:

excellent drainage required

Moisture:

dry to moderate

Notes:

prefers open, sunny habitats

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.