Yellowing older Leaves on Trachycarpus f.

I'm working on a larger residential site which is waterfront. The Windmill Palms that were planted 10 years ago have older leaves that are yellowing. To me the leaves have not reached the age to turn brown. The yellowing leaves have specs in them. I'll try and get a pic. I'm going to be going onsite to evaluate the soil but the exposure is full-sun & full ocean exposure. Anyone have any suggestions?

I'm willing to bet that you need to use addional iron. Try using some ironite. I've been using ironite for 10 years plus and swear by it. As a matter of fact, many neighbors of mine have asked me "how do you keep your palms so green" and ironite is allways the answer. I use it in addition to my palm fertilizer. It's a very light mixture (7-6-6) so you can use it through most of the year.

This message was edited Feb 7, 2006 3:49 PM

Thanks deezpalms, I'll give it a try on a test plant and see if that does the trick. I was thinking these palms are so exposed to the ocean and elements and I know they are not fond of it. Our best looking Trachycarpus are north facing amongst Rhododendrons. I'll let you know the results.

Yellow specks on the older leaves often means Potassium deficiency... common also with palms given insufficient water.

Here's a pic of the yellow trachys. As you can see the ocean is only a few feet away. So if I do a combo as mentioned above of slow-release and ironite it should improve the colour? Thanks.

You can't change the color of leaves already yellow... they will never go back to green... but you hope to keep more leaves from going that way. Only color the yellow leaves will turn are brown now. I would agree a general fertilizer wouldn't be a bad idea, but heavy on the potassium. Won't see signs of improvement probably for about a year, though.

Ok, so I need an application of general slow release fertilizer and ironite. Any recommendations on amount - should it be full strength as per the label or should it just do a light broadcast and see how it goes? I'd imagine I'm going to be climbing these trees and removing yellow leaves.

Rec: a very slow (12month) release fertilizer made specially for palms... but as for ironite, I thiink you can dump as much as you want without hurting anything (maybe 2-3 cups) and work both into the soil a few inches out to about 1'-4' from the tree trunk.

Premature yellowing of older fronds is a sign of magnesium shortage. Also be advised that Traxchycarpus fortunei is susceptible to leathel yellowing, in which case you're screwed.