Question
Recently I had an African Violet in a SE window, there was a Jade Plant and a Jasmine and a type of Philodendrum (?). The Violet ended up with a white fuzzy growth on it and also the floor was sticky, this resulted in the Jade Plant getting it in spots. I threw out the Violet, and just cut off the areas of the Jade Plant and it seemed to go away.  This was last May, now it is Feb and this Philodendrum has gotten this, I have been cutting of the areas. What I would like to know is what it is, can I spray the plants and what maybe causing it.  It is white, seem to start where the leaves meet the stems,it is very sticky, and resembles thick white cobwebs.  

Answer
Hi Joan,

Your plants have a mealybug infestation. The difficulty with treating mealybugs is that there is always more to deal with than meets the eye. Young mealybugs lack the telltale cotton-like protective coating and they are skillful at hiding in nooks and crannies where leaves and stems join. That is why they keep reappearing.

The key to successfully eradicating these creatures is to spray the ones that are out of sight. That means that whatever treatment you select, you must get complete coverage, to the drip point, of all leaf and stem surfaces of an infested plant. If you miss a few, they will live to breed another day.

You may want to try spraying with rubbing alcohol. Mix 1 part alcohol with 8 to 10 parts of water. Be sure to spray all leaf and stem surfaces thoroughly. The common practice of applying alcohol with a Q-tip is not effective because it misses the ones you can't see. It is also best if you repeat this treatment again in 5 to 7 days to catch any crawlers that you missed the first time. After that, you should check your plant weekly to see if they return.

Never spray in direct sunlight or when temperatures are above 75 degrees. It is also advisable to test any spray on a few leaves as a test before you spray the entire plant. Wait a few days following the test to see if there is any negative reaction to the spray.

Please let me know if any of this is unclear or if you have any additional questions.

Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC

You can E-mail me directly at: [email protected]

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