En EspaŅol

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

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

Evergreen flowering shrub for North Augusta GA
July 12, 2009 - I need suggestions for shade-loving evergreen flowering bush that will grow 6 feet or so, besides azaleas.
view the full question and answer

low-growing evergreen shrubs for thin soil
March 05, 2012 - Thanks to the winter freeze, we'll be starting fresh with the plants in the bed along the front of our house. The bed is about 13' long and faces the west, so it gets afternoon/ evening sun but no ...
view the full question and answer

Protection of American beautyberry in Pennsylvania
July 30, 2007 - I have had a beauty berry 2 years now. I trim it back in early spring and it returns beautifully. ...but no flowers this year and it's almost August. Last year, very few berries. Can you help? I...
view the full question and answer

Removal of non-native invasive Ligustrum japonica from Austin
February 14, 2012 - I bought a house that I am slowly turning into a native garden, but as a teacher, I have a really small budget. One entire border of my backyard (30 feet) was planted with evil Ligustrum japonica. I l...
view the full question and answer

Germination of Sophora seeds, and Dodder identification in Kingsland, TX.
May 02, 2012 - Our Mt. Laurel has just produced seeds. Can those be scarified and planted now or do they have to dry out. Also what is the stringy orange substance that gets on bluebonnets and other wildflowers ...
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