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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

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 - July 12, 2013

From: Chambersburg, PA
Region: Mid-Atlantic
Topic: Invasive Plants, Non-Natives, Trees
Title: Non-native Royal Empress tree with only green leaves from Chambersburg PA
Answered by: Barbara Medford


I have 3 Royal Empress trees in my yard that are between 2-4 yrs old and have never been any color other then big Green leaves. Do you know when they will turn Purple?


Please read this article from Ecosystem Gardening Native Alternatives to Invasive Paulownia Trees.

Paulownia tomentosa (Royal Empress) is a deciduous tree in the family Paulowniaceae, native to central and western China, but invasive in the USA. The Lady Bird Johnson Wildflower Center, home of Mr. Smarty Plants, is dedicated to the growth, propagation and protection of plants native not only to North America but to the area where those plants grow naturally; in your case, the borough of Chambersburg in South Central Pennsylvania. This places that tree out of our realm of expertise but we wanted to address your question in hopes it would discourage others from planting this non-native invasive tree.

From the Missouri Botanical Garden here is an article on Paulownia tomentosa, which said "No fall color." We found purple leaves mentioned nowhere else, although the flowers are purple.


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