Maybe Phytophthora.

More likely short of water. To verify, stick finger into an inch ofr so of the origianl rootball.

Need to put -- that is, drizzle -- water directly into rootball.

Thanks jean001a, but I'm afraid bboy is probably right. We dug it up and the roots--such as there are--are reddish and brittle. And since it was a new plant, I definitely kept it watered.

Most of the advice I've found on the web talks about replanting with a shrub that is resistant to Phytophthora. Unfortunately, I can't find a list of such plants. Any suggestions? I used the Pieris because I wanted an evergreen shrub in that particular spot.

Red roots don't equal root rot - black and dead roots do.

Further, newly planted plants (how long ago?) seldom go out rapidly with a disease.

Much more often the cause is abiotic -- that is, a non-living cause such as cultural.

Here's the list of Plants Susceptible to Phytophthora Diseases
Genus Common Name
Abies* - true fir
Alnus - alder
Arctostaphylos - kinnikinnick
Brassica -cabbage
Buxus* - boxwood
Chamaecyparis* - Port-Orford-cedar
Cornus* -dogwood
Cotoneaster -cotoneaster
Daphne* -daphne
Erica -heath
Fragaria* -strawberry
Gaultheria -salal
Ilex* -holly
Juniperus* --juniper
Kalmia mountain laurel
Lycopersicon* -tomato
Malus* -apple, crabapple
Medicago -alfalfa
Microbiota* --Russian cypress
Pieris* -andromeda
Pinus* -pine, mugo pine
Prunus -cherry
Pseudotsuga -Douglas-fir
Rhododendron* -azalea, rhododendron
Rosa -rose
Rubus* -raspberry
Solanum* -potato
Tsuga* -hemlock
Vaccinium* -blueberry, cranberry
Viburnum -viburnum
* = Commonly infected by Phytophthora

For more on this topic

Here is a link that might be useful: Pieris -- Root Rot and Dieback

I transplanted one earlier this spring, one that I had for over ten years and though I tried, it died from drought...looked just like that. It was a small dwarf and I grabbed a huge rootball but it has been so dry...

buyorsell888,
I know what you mean. This weather is brutal (boy, have I become a Northwesterner). But when we dug up this Pieris, the dirt around and within the rootball was thoroughly damp. Nothing else in the garden is showing the same signs. The Abelias and the Spirea right next to the Pieris are all doing fine.

The image at the link for Pieris doesn't look the same as OP''s plant

Toad,
Perhaps you took pictures of the rootball? (Probably not, but if you did, please post them.)

Hi jean001a,

Sorry, but I don't know who "OP" is? Link?
But if you put the photos of the dead pieris and the wilty one from bboy's OSU site together, you've got my plant.
Actually, the leaves that were still green weren't wilting so much as pulled together, pointing straight down. and there was no apparent new growth at all on the plant, though it went in in early spring. Another one (from a different nursery and planted in a different bed) showed none of these symptoms and has had lots of new growth over the same period.

And, of course, I didn't think to take pictures of the rootball. Doh.

OP means "Original Poster" the person who asked the question/started the thread.

I live in the southern part of Louisiana and planted six Southern Lady Pieris sometime in the early spring. The leaves on two of them started turning brown during the summer and they died. I decided at that point that the issue was insufficient watering. It had been dry. I watered but it must not have been enough because of the heat as the bottom of the root ball was dry. I replaced them about a month ago and have been monitoring their watering. Yesterday I found that one of the two new ones is doing the same thing. I have checked to make sure that the root ball is damp, but not wet. The soil drains well. Four of the original plants are fine and growing. All are in the same bed. They get morning sun. They were in gallon pots if I remember correctly, so they are about 12-18 inches tall at this time. Anything I can do to try to save the one currently dropping the leaves? It still has stems with green leaves, but about half of the stems are bare.

I have a similar thing happening to a pieris. Any chance you figured out what was happening and how to fix it?