Native Plants

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.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

rate this answer

Saturday - March 30, 2013
From: Houma, LA
Region: Southeast
Topic: Invasive Plants, Non-Natives, Planting, Herbs/Forbs, Trees
Title: Planting petunias around base of oak tree from Houma LA
Answered by: Barbara Medford
QUESTION:
I live in south Louisiana and I want to plant petunias. Can I plant petunias around the base of an oak tree?ANSWER:
There are 8 members of the genus Ruellia (wild petunia) native to North America, of which Ruellia caroliniensis (Carolina wild petunia) and Ruellia nudiflora (Violet ruellia) are native to in and near Terrebonne Parish in the southeastern portion of Louisiana. If you follow the plant links to our webpage on each plant you will learn that both like moist soil and can tolerate some shade. That would mean they could grow under an oak tree. BUT, you need to read this previous Mr. Smarty Plants answer about allelopathy in oaks and Ruellia brittoniana, which is the non-native Mexican petunia. Also see this Florida article about Ruellia or Mexican Petunia and note the warnings about its invasiveness.
Now, lets talk about the other petunia. Pelargonium (petunia) is a genus of 35 species of flowering plants of South American origin, closely related to tobacco, cape gooseberries, tomatoes, deadly nightshades, potatoes and chili peppers; in the family Solanaceae. From Google, here are pictures of the "other" petunia.
Frankly, we don't think either the native or non-native petunias would prosper under your oak tree, and the non-native members of the Solanaceae famly apparently need full sun, which we consider to be 6 hours or more of sun a day.
From the Image Gallery
More Trees Questions
Texas Pistachio trees dropping leaves in Austin
June 09, 2010 - I have several Texas Pistachio that are about 13 years old. Despite good rainfall in Travis county this year, they seem to be losing most of their new leaf growth now in early June. Leaves are simpl...
view the full question and answer
I need a tall tree with kind roots for a narrow space
March 11, 2009 - We have a space in the yard where a building is within 3 to 6 feet of where we would like a tall tree. What tree could achieve two stories in height, while not messing with the foundation of the bu...
view the full question and answer
Leaves dropping on evergreen sumac in San Antonio
January 11, 2012 - I have a large evergreen sumac in my back yard that started off as a small shrub 10 years ago. This summer the leaves turned red and now have dropped off. Is the plant dead? It sent out two smaller pl...
view the full question and answer
Privacy screen from Temecula CA
May 04, 2013 - I live in Temecula and need a fast growing tree by our pool that is good to block neighbors house.
view the full question and answer
How can I prune my Texas Mountain Laurels to be more tree-like?
March 24, 2011 - I planted several Texas Mountain Laurels last spring and would like to train them to be more tree-like rather than shrub-like. Each is around 36" tall with 5-10 trunks coming from the ground. Where...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |