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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


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


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. 

Read our previous answer in full.


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