En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - How can I distinguish Hibiscus laevis from Pavonia braziliensis in New Braunfels, TX?

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.

Need help with plant identification, visit the plant identification page.
 
rate this answer
1 rating

Monday - September 12, 2011

From: New Braunfels, TX
Region: Southwest
Topic: General Botany, Plant Identification, Shrubs
Title: How can I distinguish Hibiscus laevis from Pavonia braziliensis in New Braunfels, TX?
Answered by: Jimmy Mills

QUESTION:

How can I distinguish Hibiscus laevis (Halberdleaf Hibiscus) from Pavonia braziliensis (Brazillian Rock Rose)? Earlier this year I was given the former by a friend and former NPSOT chapter President. Then I bought a Salvia at Medina Garden Nursery, and it had a "volunteer" in the pot that they identified as "South American" Rock Rose. Now both are blooming, and they appear almost indistinguishable. Thanks,

ANSWER:

Both Hibiscus and Pavonia are genera in the plant family Malvaceae, so you would expect them to resemble one another; one source referred to them as cousins, but lets not go there. When Botanists describe plants and assign them to genera and species, a great deal of attention is paid to the structure of the flowers in addition to other morphological and chemical characteristics. There is one difference in the flowers of these genera that is easy to see, and will allow you to distinguish Hibiscus from Pavonia. Luckily, you have flowers of both plants.

Before we go into flower parts, look at this diagram to refresh your memory. We are interested in the pistil which is composed of the ovary, style(s) and stigma(s).

One character that separates the two genera is the number of stigmas at the tip of the pistil. Plants in the genus Hibiscus have the style divided into 5 stigmas, while plants in the genus Pavonia  have twice as many stigmas (10).

In the case at hand, the common name of Hibiscus laevis (Halberdleaf rosemallow), or Halberdleaf Hibiscus gives us another clue. The halberd was a type of pole axe used in the middles ages, whose shape somewhat resembles the base of the leaf of H. laevis (or vice versa).

The following links illustrate these features:

Alabamaplants.com  pictures of the stigmas and leaf shape in H. Laevis.

Greatstems.com  pictures of stigmas of Pavonia braziliensis

Greatstems.com  good illustration of stigmas in a Texas Pavonia, P. lasiopetala. Also note the leaf shape

 

More Shrubs Questions

Smarty Plants on lantana in Dallas
September 14, 2005 - For several years, the lantana plants in my backyard in Dallas grew and bloomed all Summer and Fall until the first real cold snap. I've loved having a native plant that didn't need constant care a...
view the full question and answer

Plants for a bank too steep to mow
June 24, 2009 - Like the inquiry made in late June of 2008, mine involves a bank that is too steep to mow. However, ours is facing south. I am looking for a native grass, plant or groundcover. Any suggestions? ...
view the full question and answer

Non-berrying possumhaw from Austin
June 05, 2014 - I planted a possumhaw 8 to 10 years ago for the beautiful winter color, it has never set berries. I see tiny white flowers along the branches each spring, and always hope this will be the year, but I...
view the full question and answer

Recovery of an agarita having been cut down from San Antonio, TX
August 16, 2013 - I had an agarita adjoining a cedar and a volunteer hackberry in my yard. The tree trimmers were supposed to cut out the hackberry but unfortunately also cut the agarita back to the ground. How long ...
view the full question and answer

Nutrient imbalance in Tecoma stans
October 18, 2007 - I have two Tecoma stans on the north-east side of my yard. They have grown very tall (5') but have not bloomed all summer. Last summer they bloomed profusely. Any idea what the problem might be?
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center