My seedling has been growing, but one day early August I noticed a little hole starting to form. Over the course of about a month it has gotten bigger. I have attached pictures with date to show the progression of my concern. What do you think is going on?

Looks like a fungus to me. Maybe too much water down in the crown? It should be okay but I’d try not to allow any water down into the top of the palm. If those spots grow or continue on the new growth you may want to put some fungicide down there to clear it up. It looks to me that its already cleared up though. Just monitor that new leaf. 

If its not fungus, be watching for catipillers like things, they are tiny but they swoop in and eat and you don't usally see the damage until they do it

Definitely looks like a chewing insect damage. The palm looks healthy otherwise. 

Thank you!

Sometimes I see damage in the meristem manifest weeks later in bruised of dead tissue. Not saying this is for sure that, but something to take into consideration when assessing a palm.

This is the current state. Just took pictures. I moved it as suggested to a less wet location.

Anyone have any thoughts?

SUNBURN!

 

aztropic

Mesa, Arizona 

Yeah the reddish-brown color is typical of sunburn.  That can happen due to high temps/low humidity, extra reflected light off of the white wall, or just moving it out into more PM sun, etc.  Coconuts should acclimate to more sun with the next leaf, since they can grow in full sun at a young age.

@aztropic @Merlyn What would you all do to help get it back on the right course?

If it has been in that spot for a couple of weeks and the bronzing isn't getting worse, then that's probably the limit of the sunburn.  The next leaves should grow out more sun-hardy, and of course it'll grow faster with more sun.  The real sunburn problems come in with palms that really prefer shade, like the multiple recent Chambeyronia sunburn threads here.  But they have coconuts in full blazing sun from a young age around here.  If you are in a dry area I'd just match the higher temps of summer + sun with a bit more water.  I'd also mark the new spear horizontally with a sharpie so that you can see if it's growing consistently.  If it is growing on a semi-daily basis then I'd leave it alone and the next leaf should grow out nicely.  If it is *not* growing or if the bronzing is getting much worse day by day, then a shadier spot would be a better choice.