Foxtail Palms and winter sun - sickly tree - suggestions?
Howdy, I'm Coach Dave and I work for The Home Depot and I think your problems can be solved.
Your options are pretty numerous in terms of the quick fix, but let's take a look outside the box on other options:
1) Re-locating the palm to a sunnier area is an option.
2) Perhaps get an outdoor full spectrum halogen spotlight to add light during the night. This has the light that can add light close to sunlight.
3) Wait and see if the season change will take care of the problem by itself might be your answer?
Pruning other palms during the winter is an accepted practice for old growth, however do not trim the new growth. On the chance that your palm doesn't make it, replacing a Palm is never a bad idea.
As for fertilizer, Manganese is the best thing for palms. I recommend Epson Salt as a good source of Manganese, but a slow release "Palm Fertilizer" will work much longer.
I hope this helps you with your "Finicky Foxtail". If you have more questions just ask.