I have a lot of Roebellini Palms in my garden and most of them seem to be sick. The new palm leaves that are sprouting from the center of the tree are coming out brown and dead looking. See photos below:

Is it not too late to save these trees? What can I do?
I have already tried to spray some copper fungicide on the affected leaves (a couple of times now), but maybe I am not using enough fungicide. I have a total of 10 bunches of them (each bunch has 2-3 trees in it) and I have used one medium sized copper fungicide for all of them, is that too little?
I have also applied some palm fertilizer to them. Any idea what else I could do to save them? Or maybe they will just recover by themselves. I think the seller who I bought the house from had just recently planted them, so they are still young I suppose.
The only other thing I can think of is that perhaps they have not been planted deep enough in the soil, here is a pic of how the trunk is planted in the soil:

Any ideas?



Is it not too late to save these trees? What can I do?
I have already tried to spray some copper fungicide on the affected leaves (a couple of times now), but maybe I am not using enough fungicide. I have a total of 10 bunches of them (each bunch has 2-3 trees in it) and I have used one medium sized copper fungicide for all of them, is that too little?
I have also applied some palm fertilizer to them. Any idea what else I could do to save them? Or maybe they will just recover by themselves. I think the seller who I bought the house from had just recently planted them, so they are still young I suppose.
The only other thing I can think of is that perhaps they have not been planted deep enough in the soil, here is a pic of how the trunk is planted in the soil:

Any ideas?