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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.

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Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

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Friday - June 29, 2012

From: Prosper, TX
Region: Southwest
Topic: Non-Natives, Pests
Title: Application of sprays to non-native Crape Myrtle from Prosper TX
Answered by: Barbara Medford

QUESTION:

Can applying a systemic insecticide/fungicide combo prevent or limit Crape Myrtle blooms? I have 5 large lavender Crapes that are not blooming or budding yet and this is the first time I have used a systemic on them. Applied it in late May. They do have new growth and are very full.

ANSWER:

 

Lagerstroemia indica (crape myrtle) is native to China, Japan and Korea and is therefore out of the realm of expertise of the Lady Bird Johnson Wildflower Center, home of Mr. Smarty Plants. We are committed to the growth, protection and propagation of plants native not only to North America but to the area in which those grow natively. This is a conservation issue, because plants native to an area will have become accustomed to the soils, rainfall and climate over centuries of experience.

From the United States National Arboretum, here are Questions and Answers on Crape Myrtle. From that article:

"My crapemyrtle is reluctant to bloom. What am I doing wrong?

Crapemyrtles flower most heavily in full, uninterrupted sunlight.  Even an hour of shade during the day will compromise flowering.  Frequent irrigation, lack of heat, and overfertilization promote vegetative growth at the expense of flowering.  In extreme drought conditions or cool, rainy summers, flowering may be delayed until the early autumn."

We also discourage spraying any kind of "...icide" to a plant without clear indications that it is needed.

 

 

 

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