Native Plants
![](../_images/smarty_plants.gif)
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.
![](../_images/mr_smarty_plants_logo_web_200w.jpg)
rate this answer
![](../_images/star_00.gif)
Friday - October 28, 2005
From: TULSA, OK
Region: Southwest
Topic: Non-Natives
Title: Hours of darkness for non-native poinsettia to bloom
Answered by: Joe Marcus and Nan Hampton
QUESTION:
I have a poinsettia from last Christmas still alive. I was told to get it so many hours of darkness. Do you know how many hours? When would be the best time to start displaying the plant again?ANSWER:
The poinsettia (Euphorbia pulcherrima) is native to southern Mexico. They are "short-day" plants which means that flowering is in response to long nights. It varies among cultivars, but 16 hours of uninterrupted darkness per night for several weeks is sufficient to induce the flowering response in any poinsettia. Any light at all will delay or stop the flowering response. There are classic stories about automobile lights from nearby highways and even flashlights from night watchmen delaying flowering on greenhouse grown poinsettias. People commonly put their plants in a dark closet each night for a few weeks in the fall to induce flowering and the red bract development (they bring them out each day). It is a little late to get your plant to flower by Christmas, but you can still get it to turn red just the same. If you start now, it may be red in time for St. Valentines Day! You can read more about the care of poinsettias.More Non-Natives Questions
Treatment of leaf curl on non-native peach in Camano Island, WA
April 26, 2009 - How to treat peach leaf curl?
view the full question and answer
Division of non-native Lamb's Ear plant in Austin
May 17, 2010 - I have a lambs' ear plant that has gone wild, and I would like to divide and transplant part of the plant. Advice? Live in Austin, TX. 78757
view the full question and answer
East Texas grasses for holding soils
September 17, 2008 - Hi Mr. Smarty Plants,
I have a question about the East Texas area: Specifically, which natvie grasses can be planted to hold the soil/new roads through the winter?
Here is the situation: (Against...
view the full question and answer
Problems with non-native nectarine in Gilbertsville PA
November 20, 2009 - I live in southeastern Pennsylvania. I have a mature nectarine tree maybe 14 years old. It has a greenish grey spotting on the trunk and branches, the fruit always turns into the brown mummies and f...
view the full question and answer
Leaf-cutter ants on non-native crape myrtle
May 08, 2008 - We have a problem with cutter ants. I lose my entire Crepe Myrtle tree every year. All of the pest control personnel I ask do not have a solution. Can you please suggest something to eradicate thes...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |