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?


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
4 ratings

Sunday - January 31, 2010

From: Austin, TX
Region: Southwest
Topic: Non-Natives
Title: Non-native Dietes bicolor leaves brown after freeze in Austin
Answered by: Barbara Medford


I live in Austin, and my butterfly iris (Dietes bicolor) that I've had for the last 6 years are all turning brown after the most recent freeze. Should I cut them back, with the thought being they would sprout new growth? Or are they dead, and should be dug up and replaced?


Dietes bicolor, Butterfly or African iris, is a native of South Africa, and therefore out of the purview of the Lady Bird Johnson Wildflower Center, where we are dedicated to the use, care and protection of plants native not only to North America but to the area in which they are being grown.  Both it and members of the genus Iris are related distantly by being part of the family Iridaceae. We can tell you that the Dietes is hardy from Zones 8b through 11; they are evergreen through the winter unless the temperature goes below 25 deg. F., at which time the leaves will turn brown. Since this plant regenerates from a rhizome, it will no doubt come back in warmer weather. We would suggest simply trimming down those browned leaves and not fertilizing.

More Non-Natives Questions

Salvia that needs dividing in Maryville MO
April 09, 2010 - I have some May Night salvia that is 3 years old. Last summer it split in the middle and spent a lot of the summer laid open. I'm wondering if it needs to be split or pruned in some way?
view the full question and answer

Question about non-native tree hardiness
March 06, 2009 - Hi there, im wondering if you can help me. Which of these plants can grow on poorly drained soils. Tamarix Tetandra, weigela 'moulin rogue', ulex europaeus or salix alba?
view the full question and answer

Hurricane resistant alternatives to crape myrtle
September 02, 2007 - Are there any native small to medium trees (15-25 ft) to use instead of crapemyrtles (Lagerstroemia indica)? Crapemyrtles come in many colors and bend with hurricane winds instead of snapping or uproo...
view the full question and answer

Growing non-native Knockout roses and golden euonymus together from Crystal City MO
May 19, 2013 - Can you plant knock out roses and golden euonymus together?
view the full question and answer

Problems with non-native weeping willow in Greenville NY
September 10, 2009 - We live on the border of Zones 5b and 6a and have a weeping willow that grew so much in only 3 years and did quite well. However, there are aerial roots growing on its bark as well as part of the bark...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center