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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 15, 2007

From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders
Title: Whitefly infestation in roses and salvia
Answered by: Joe Marcus

QUESTION:

Several of my outdoor plants (including Knockout roses and salvia) have a white residue on the stems. If I touch it a white bug jumps off. The residue can be wiped off or sprayed off, but the little bugs just return and back it comes. The bug look almost like a tiny moth.

ANSWER:

The pest you described is probably Whitefly. Whiteflies are persistent and pernicious pests that have become a more serious problem in recent years. Happily, there are any number of biological, non-chemical and chemical control methods for you to choose from to rid your plants of these pests. Which method you choose will depend on your personal preference and the conditions in your garden. Any of the better garden centers in your area will be able to advise you on your choices.
 

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