Sun damage often burns the leaf surface and sometimes deeper into the leaf tissue.

Over the winter, the breakdown of those dead cells continues. A white layer, which flakes off later on, develops.

So, if that's the white you're talking about, it's a normal sequence.

That said, it would help us if you would post a picture. Is that possible?

Leaf miners eat the chlorophyll causing the leaf to turn white and eventually brown.

A grayish white, powdery coating or fuzzy white growth on upper or lower surfaces is Powdery Mildew.

Here is a link that might be useful: How to grow rhododendrons and azaleas.

It would seem that we need a picture. Is it possible?

I think you might be right on with the leaf miners, the leaves are white and then turn brown. I posted a link, there are two photos, the link I posted ends with rhodo1.jpg, there is also a rhodo2.jpg (http://www.cdesignlab.com/private/rhodo2.jpg).

So if that's what it is, how do I get rid of them? I have two cats that go out back so I'd like to avoid really harsh pesticides if i can.

Thanks!!!

Here is a link that might be useful: {{gwi:388947}}

Not leafminers. Not a disease.

But ran short of water last year, then the leaf tips dried back.

The rest of the story is as I explained for sunburn, above. Over the winter, the breakdown of those dead cells continues. A white layer, which flakes off later on, develops.

Both photos show just that. Especially the 2nd one, where the dead cells have fallen out.

Oh yes, thanks for the pictures. Because of them, you have an accurate diagnosis rather than several guesses.

Took a second look at the photos. The dead leaf tips is rootball ran short of water. but the dead spots toward the center of the leaves is a result of sunburn.