Why are my holly bush leaves turning brown and falling off?
Usually brown leaves signify that the plants need more water. You said that you haven’t been in a drought situation, but I still think you may want to supplement the water around the plants. Also, I would recommend using a root stimulator solution on all three plants once a month for at least six months. As long as the bark is still green, the plants are alive and even if they lose all or the majority of the leaves, when your spring arrive, they should leaf back out. Just remove the brown leaves, use the root stimulator, plus, you can use a weak solution of a water soluble fertilizer (like Miracle Gro), and I think your bushes will snap out of it. Good luck, and I hope this information helps.