Santa Cruz Tarplant ⚠️ Threatened

Holocarpha macradenia

Native to:
United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Asteraceae
Genus:
Holocarpha
Species:
Holocarpha macradenia
USDA Symbol:
HOMA

Growth Characteristics

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

Wildlife Benefits

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

Garden & Ecology Notes

Wildlife Value:
bees, butterflies
Deer Resistant:
Yes
Fragrant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Native to California coastal prairie and grassland habitats historically maintained by fire; resprouts or regenerates from seed bank post-fire.

Soil Requirements

Soil Type:
sandy, well-drained, nutrient-poor soil
pH:
6.0 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
native to coastal prairies and open grasslands

Propagation & Germination

Stratification:
None required
Germination Time:
14–30 days
Notes:
Seeds germinate readily with fall rains in Mediterranean climate; light may enhance germination.

The above propagation data sourced from Claude AI