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.

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer

Not Yet Rated

Wednesday - December 02, 2009

From: Marble Falls, TX
Region: Southwest
Topic: Non-Natives, Planting
Title: Hardiness of Euphorbia milii from Marble Falls, TX
Answered by: Barbara Medford

QUESTION:

What is the hardiness of euphorbia mili, crown-of-thorns?

ANSWER:

We answered and then corrected our answer on a very similar question just today. From that, here is the situation on the hardiness of Euphorbia milii, Crown of Thorns:

"Euphorbia milii is only hardy from Zones 9b to 11. Central Texas is generally Zone 8a. The plant itself would be threatened by a hard frost in this area, and certainly a plant with its roots exposed in a pot would be even more likely to be damaged by cold weather. Euphorbia milii should be treated as an indoor potted plant over the winter. Here is more information on this plant from Floridata and pictures from Google."

This plant is actually a native of Madagascar, and out of our range of expertise at the Lady Bird Johnson Wildflower Center, where we deal only in plants native not only to North America but to the area in which they are being grown.