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Sunday - July 06, 2014

From: Georgetown, TX
Region: Southwest
Topic: Invasive Plants, Problem Plants
Title: Is Ruellia aggressive?
Answered by: Nan Hampton

QUESTION:

Is Ruellia aggressive?

ANSWER:

There are 5 native species of Ruellia in the Central Texas area.  All of these occur in or adjacent to Williamson County.   None of these could be said to be aggressive or invasive.  These 5 species are:

Ruellia drummondiana (Drummond's ruellia)  Here are more photos and information from the School of Biological Sciences, University of Texas at Austin.

Ruellia humilis (Fringeleaf wild petunia)  Here is more information from Missouri Botanical Garden.

Ruellia metziae (White ruellia)  Here is more information from BackyardNature.

Ruellia nudiflora (Violet ruellia)  Here is more information from the Image Archive of Central Texas Plants and Southeastern Arizona Wildflowers.

Ruellia occidentalis (Western wild petunia)

However, the non-native Mexican species, Ruellia caerulea [synonyms=R. brittoniana, R. simplex, R. simplex] (Britton's petunia) is on the Texas Invasives list and the University of Florida's Center for Aquatic and Invasive Plants list and is definitely aggressive.  Its seed dispersal mechanism is one reason that it is able to invade new areas so easily—the seed capsule explodes and the seeds can fly long distances, as far as 30 feet.  Ruellia caearulea is the petunia most likely to be sold in large commercial nurseries.

 

From the Image Gallery


Violet ruellia
Ruellia nudiflora

Prairie petunia
Ruellia humilis

White ruellia
Ruellia metziae

Violet ruellia
Ruellia nudiflora

Western wild petunia
Ruellia occidentalis

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