Sorry to hear this 25-yr old plant is having troubles, Sooz. I hope it is just not getting enough moisture. I had a similar problem with a smaller shrub when I turned off the automatic sprinkler because the temperatures were going to be at or below freezing. Our winters are mild too so, eventually, the temps went back to the 50s and "someone" forgot to turn back on the sprinkler. It was a dry winter that year so surprise-surprise! when I noticed the shrub had lots of browned out leaves.

There could be other reasons of course. But I would start checking the soil for moisture problems first (too much water can cause root rot; too little water dries out the buds, leaves and stems).

Turning on the sprinkler saved my bush. The brown leaves were eventually replaced by new ones and, in two years, you could not tell that this had happened.

The same thing can occur with potted plants that sit in potting soil that drains too well and that does not keep some moisture for the plants. Example: potting soil made with too much sand.

How do you tell if it is still alve? You can prune a stem in 1" (or 2") increments until you hit green. That should help determine if the plant is still alive. Maintain the plant mulched with 3-4" of mulch and water it when a finger inserted to a depth of 4" feels dry or almost dry. Check it weekly. More often if the area is windy.

And my last two suggestions: (1) look at the underside of leaves (fallen and otherwise) and determine if there is a tea scale infestation going on; (2) go to the link below for more information on a fungal infection called camellia canker and dieback.

Does this help you, Sooz?
Luis

Here is a link that might be useful: Camellia Dieback

Thanks, Luis for the very helpful info and the link! I'll pass the info to our friend and see if we can figure things out!
Smiles,
Sooz