Outside in full sun in Baja California 10 feet high
This will indicate that there, either, were flowers or they are flower buds that will bloom soon. I cannot see very well from that photo.
I live in Arizona. Its been 105+ for many weeks, with no rain. I have been watering my M-palm twice a week. Am I under watering it? Please see pics.
This looks more like overwatering. These are very drought tolerant, but they are not tolerant of overwatering. I would be sure that the soil is completely dry over half way down the container before watering. You may need a fungicide, as well.
These articles will help:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
The tallest stalk is approximately 5 feet tall and somewhat shriveled about 2 feet from the top.
Unfortunately, your photos did not come through. The course of action depends on what is wrong with it.
It could be in need of repotting, or it could have a root infection, or it could be, simply, out of food in the soil.
Typically, the problem will be with infection from overwatering. This is easy to do, since most will treat this as a palm, and not as the succulent that it is.
Treating this like a desert cactus will ensure that it remains healthy, ans sometimes it can take years to show damage.
Another thing to consider will be soil nutrients. Test the soil. It should contain a low amount of nutrients, but not be lacking completely. Alternatively, overfeeding will cause issues as well.
This article will offer more information:
https://www.gardeningknowhow.com/houseplants/madagascar-palm/madagascar-palm-care.htm
Hi! I’ve had my small Madagascar palm for close to two years now; it looks healthy, it hasn’t done anything unexpected and I haven’t seen any problems with my plant. However, it isn’t growing much at all. I’ve been keeping it directly under a grow light when it’s inside, and it’s in full sun when outside during the summer. The only change I have witnessed is it dropping its leaves and then regrowing them in the spring. I water sparsely. Am I doing something wrong? Does it grow extremely slowly?
They go dormant during the winter and drop a few leaves. In spring, give it some fertilizer and see if it doesn't start growing. They are slow growers, especially in containers. (Our article says it can grow a foot a year, but I couldn't find that anywhere else. All other sources said slow growing.)
https://www.gardeningknowhow.com/houseplants/madagascar-palm/madagascar-palm-care.htm
https://www.south-florida-plant-guide.com/madagascar-palm.html
Is there a paint I can use to protect it?
There is! Here is an article that will go into more detail:
https://www.gardeningknowhow.com/ornamental/trees/tgen/painting-tree-trunks-white.htm
My plant also has a dime size brown hole on the top of the main shoot. It only gets watered about every four months or so.
Unfortunately, it seems to be suffering from an infections. This could mean that the soil is compacted under the decorative rock. You may have success adding earthworms to the area, but you will need a fungicide to correct the rot issue, for sure.
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/houseplants/madagascar-palm
Broke two shoots off of a healthy plant grown outdoors looking to transplant into two healthy ones and I already potted immediately after I broke them off and it’s not looking good so I did some research (I know after the fact) to looking into saving them. There’s new leaf development in the short time but more leaves are looking unhealthy and the base of injuries As wellZ
I would treat it like a succulent or cactus.