Sundrops, Hartweg's - Calylophus hartwegii

(Western Primrose)

Family: Evening-Primrose (Primulaceae) Native


In front of Visitor Center (N35D33'01.302 X W105D41'08.772)

Flowers first observed: 8/16/17

The Plant w/Flowers

The Flower


"USA:  AZ ,  CO ,  KS ,  NM ,  OK ,  TX 
Native Habitat: Prairie, Plains, Meadows, Pastures, Savannahs" (


"Water Use: Low 
Light Requirement: Part Shade 
Soil Moisture: Dry 
Soil Description: Clay, Clay Loam, Medium Loam, Sandy Loam, Sandy, Limestone-based, Gypseous, Caliche type 
Conditions Comments: Somewhat upright and bushy plant with narrow leaves and soft yellow cup flowers that open in the evening and close the next afternoon shortly before new flowers open. This plant prefers fast draining soil and loves reflected heat making it an excellent choice for a rock garden or rocky slope. Deadheading and giving it some summer water will prolong the flowers. Cut back to 6-8 in the autumn to reshape." (

Ethnobotanical Uses


"Navajo, Ramah Panacea Plant used as 'life medicine,' especially for internal bleeding." (Moerman 133)

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