Good eye. The irrigation head you see in the photo is a remnant from the previous garden that was in this area. I did not bother to dig it up and left in in place. Its never used anymore. I like the idea of the boulder that could work. As the rains will be arriving soon I suspect as you suggest that when the soil gets wet things will start moving again.
It is firmly in place where it is now though as I have tried to move it to see how loose it is and it does not seem loose at all. Maybe this years new roots have a strong grasp of the ground.
For this plant I did not place the gravel in the hole like I did the other two. Looks like it may be a lesson in how important the hole preparation really is.
I was hoping maybe too that as the foot gets wider it might "fill in" under where its leaning and support itself? Maybe that is wishful thinking...
Maybe a few bags of gravel as mulch around the whole area could work too just to get some weight on things?
