Posted this in the "trees" forum before I realized there was a tropical tree forum.
In December, I believe, hubs bought two lovely little coconut palms for my (then) new garden. Set them inside the pallet fence and went to run errands. Came back and saw the campus puppies had squeezed through the pallets to chew on the trees, breaking them up pretty bad. But the roots seemed interact, so I planted them.
Goats got in and nipped the fuller leaves, then got in again (all holes have now been plugged) and ate off all remaining green. I watered and tried to baby them for several months. Was finally giving up, and up pops green leaves on both of them. But that was a couple of months ago, and growth is EXTREMELY slow. The new leaves are sticking up only a few inches from the ground.
Coconut palms are extremely slow growing. Real sloooooow. They grow fastest when they have excess to frequent water, or even have their deepest roots in water. So keep them watered and they should recover, but it will be a slow process.
I planted a sprouted coconut the day I moved to my present property. It's been over 15 years ago and the thing isn't even out of the shrub stage yet. I may not live long enough to see it look like a small tree.
There are other palms that grow much faster, but coconuts are slow growers.
It's never too late to start! I retired to homestead on the slopes of Mauna Loa, an active volcano. I relate snippets of my endeavor on my blog : www.kaufarmer.blogspot.com
What is the condition of the soil these are residing in?
As Su Ba brought up, coconut palms are slow growing in the best of times. (Date Palms are not much faster growing but they are faster)
Root development is mandatory for the coconut palm to thrive, so I would recommend you get some mycorrhizae in and around the root system, that will really make a difference that is noticeable in the coconut palms.
It sounds like they will survive the brutality, they have endured so far, now it is time to give them some soil TLC with mycorrhizae, perhaps some EM as well (not as important as the mycorrhizae).
The soil is clay, quite heavily supplemented when they were planted, with organic material (not by me, but I did see). I've mulched them quite a bit and try to give ample water. I have some 2 or 3 gallon jugs (what cooking oil comes in here) that I'm going to puncture with a nail once, dig down so only the cap is above ground, and situate them 6 inches or so from the tree roots. I have to put them on a bed of sawdust to make sure they don't get clogged, but that makes a good "drip irrigation" system for the trees. I should get by with filling the jugs every couple of days.
I did put a bit of sea salt a few inches around the base and watered it in. I've also fertilized them with urine which they seem to respond positively from.