Hartweg's Sundrops

Calylophus hartwegii

This lovely Southwestern native offers narrow leaves and soft yellow cup-shaped flowers that open in the evening and close the next afternoon shortly before new flowers open. An excellent choice for a rock garden or rocky slope. Drought tolerant once established.
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Good to grow...for one season:


Once established, needs only occasional watering.

We no longer grow this plant

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Botanical Pronunciationkal-ee-LOW-fus hart-WEG-ee-eye
Average Size at MaturityReaches 1 ft. tall, 2-3 ft. wide.
Bloom TimeYellow flowers spring to fall.
Deciduous/ EvergreenEvergreen
Flower AttributeShowy Flowers
Water NeedsLow
Watering NeedsOnce established, needs only occasional watering.

Thrives in lean to average soil. Follow a regular watering schedule during the first growing season to establish a deep, extensive root system. Clip spent flowers to promote continued bloom. Cut back to the ground at the end of the season.

Your USDA Cold Hardiness Zone:

Good to grow...for one season