Question
we have a white powdery substance on some of our Mediterranean palms. What is it and how do I get rid of it? I can wipe it off with my fingers.  The middle new leaves seem very covered and are dead.

Answer
Howdy Karen,
Coach Dave here and I work for The Home Depot in California. I deal with palms on a daily basis and this is a common question. While your Mediterranean (European) Fan Palm Trees (Chamaerops humilis) might be pollinating, this most likely is a pest. Spider Mites or Scale are the usual culprits that can end the life of your plant. Here are the steps I recommend for saving your palms.

1)The physical size of usually dictates how much of the palm you can prune. I usually prune off dead fronds in any area I can physically trim starting on the bottom. Be careful not be over zealous, the plant can suffer shock from too much trimming.

2)The most effective way kill the active bugs is with a petroleum-based spray found at most home improvement centers. Insecticidal soap never works for me with an infestation of Scale.

3)Make sure to decontaminate your pruners/saws/loppers in between plants so as not to spread the problem.

4)The petroleum-based spray will take at least 2-3 applications about a week apart. I would recommend using an alcohol wipes to take the large amount of dead bugs off the day after every spraying.

If you have any other question please let me know, I'm glad to help.

Yours Respectfully,

Coach Dave