Have a few of the "Guadalupe Island" palms in the ground for two years. Our hundred year freeze toasted a couple, the remaining three have not really taken off. The leaves start off OK but quickly get rusty brown and yellow streaks, then eventually dry up.

They get watered every 5 days in the hottest part of the summer - 4 2gal emitters per tree, about a foot away from the trunk, on for 2 hrs (16 gal per tree). Fertilized 1x spring, 1x summer (overdue for summer, oops.) Sadly, this is the best of the three. Any advice? About to give up on these, and they were not cheap, see pics...

Palm trees need potassium in large amounts. Potassium deficiency is perhaps the most widespread and serious of all disorders of palms. Usually potassium deficiency affects older leaves on the palm tree first, than progresses to the newer leaves higher up on the tree as the problem becomes more severe. You will notice translucent yellow to orange spots. There also can be black or necrotic spotting. Leaflets will usually have areas of necrosis (dead tissue) along their margins and tips. Applying the required potassium will correct the deficiency, but the damaged fronds will always remain damaged. - Millet (210 BO-)

Thanks for the reply, Millet.

I'm using Arizona's Best Palm Tree 10-5-10 http://www.gro-well.com/lawnandgarden/products/arizonas-best-palm-tree-fertilizer-5lb.html

Should I use it more often (say monthly during growth season), or switch to something with a higher K ? I like to use their products, since they have ingredients that help with our piss-poor soil, are widely available, are economical...and they are located here in AZ.

10-5-10 should be fine, just fertilize more often. Palms also frequently suffer from magnesium deficiency. Does your fertilizer contain magnesium? If not use Epsom Salts (Magnesium Sulfate). - Millet

I agree, palms are heavy feeders.