Question
We live in Florida and keep our Potho Plants on our balcony.  We transplanted both plants using Hyponex potting soil.  Now our plants have some type of white substance (like flakey green moss but only white)appearing on the leaves and stems.  Could it be coming from the bark that the plant attaches itself to.  Please help save our Potho's.

Thank you.

Answer
Hi Robbin,

From your brief description, I believe that your Pothos may have in infestation of mealybugs. Mealybugs have a soft, cotton-like texture.

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.

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. If you miss a few, they will live to breed another day.

I do not recommend any pesticides because they are all hazardous to use and not 100% effective against mealybugs. The best non-toxic treatment for mealybug is called Brand X foliage cleaner (Yes, that's for real). It is available through Southwest Plantscape Products in California (www.southwestplantscape.com ). Their phone is 1-800-333-7977. It is a silicon-based product so it is very slippery. Its ability to penetrate is probably the key to its effectiveness because it gets into the tiny crevices that other sprays miss.

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.

Another option is to wash the plant down with soap and water. Use the same dilution as when washing dishes. Apply in the same manner as rubbing alcohol.

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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