Rothrock's Knapweed

Plectocephalus rothrockii

Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Asteraceae
Genus:
Plectocephalus
Species:
Plectocephalus rothrockii

Growth Characteristics

Life Cycle:
Annual
Growth Habit:
Forb/herb
Height:
1-2 ft
Light Requirements:
Full Sun
Drought Tolerance:
High
Bloom Months:
mar, apr, may, jun, jul, aug
Bloom Colors:
purple

Native Range

United States: Arizona, New Mexico

Soil Requirements

Soil Type:
well-drained, sandy or rocky soil
pH:
6.0 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
native to arid and semi-arid regions

Germination Information

Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).

Source: OpenAI GPT-4o