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Mexican petunia

Ruellia brittoniana


The Mexican petunia is a low mounding perennial with long dark evergreen leaves and purple-blue flowers that cover the plant from spring into summer. This species grows 12-15 in. high and to 24 in. wide with a compact habit. One popular cultivar, R. b. ‘Katie’, is smaller with a mature size 12-15 in. in height and 15-18 in. wide. These plants are valued for their attractive foliage and large purple petunia-like flowers.

This southwestern native grows best with regular water and protections from hot sun exposures. It is cold tolerant, surviving temperatures below 20°F, and maintains good foliage character throughout the year.

Plant Type: Perennial
Foliage Character: Evergreen
Habit: Mounding, Compact
Growth Rate: Moderate
Foliage Color: Dark green
Flower Color: Purple
Flower Season: Summer, Spring
Soil Adaptations: Well-draining soil, Sand, Clay
Exposure Adaptations: Morning sun, Heat, Frost, Partial sun
Function: Rock gardens, Hummingbird plant, Flowering accent plant, Container plant, Small spaces, Borders
Height: 12 in. – 15 in.
Width: 24 in.

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