Is there anyway you can post a picture? Without seeing it I would say transplant shock. How big where the roots when you planted it. If the roots here cut the palm is sending all the energy it has to the root system. I would want to see a picture but a mild root stimulator might help for the long run. I would be careful not to fertilize if it were mine, I toasted a 2 robustas last year from a mail order place. If I think back one of our members from Michigan might have had the same problem with a 7' windmill his name is palmmandan I'm pretty sure he might be able to help.

Bill

You probably made the soil even worse when you added pea gravel into it. The weight of the gravel actually compacts common peat-based potting mediums which lessens the aeration in the soil. A good soil addictive would be perlite.

You've got worms? Earthworms are fine, but lots of other worms aren't.

So do I need to dig them up and add perlite?

Yes I have earthworms the soil there is very humus. I called the guy that sold them to us and he said to add 1/2 cup of epson salt. So I did, how often do I add epson salt? The windmill has no fronds left, but a shoot is coming up. The pindo every last one is dead even the shoot in the middle and the only one that seems to be holding on is the Saw Palmetto

So do I need to dig them up and add perlite?

Yes I have earthworms the soil there is very humus. I called the guy that sold them to us and he said to add 1/2 cup of epson salt. So I did, how often do I add epson salt? The windmill has no fronds left, but a shoot is coming up. The pindo every last one is dead even the shoot in the middle and the only one that seems to be holding on is the Saw Palmetto

Can you post pictures of the plants and/or soil? You may have something else wrong such as a disease. Unless you need magnesium, it doesn't make sense to only apply Epsom Salt.