I'm no Rhodo expert but they like well draining soil, moisture, and low pH. I'm not sure what your problem is?

My guess it the pH is off. Ask at a good local garden center how you can get a soil pH test. The other rhodys may be more tolerant of a high pH, or planted in a sea of peat.

Lacebug is a pest on Rhodos.......any sign of this?

http://www.puyallup.wsu.edu/plantclinic/resources/pdf/pls120rhodylacebug.pdf

Another Rhodo problem is phytophthora root rot.

thanks to everyone. I have a lot of work to do . . .

Was it mulched over the winter, and were you careful to keep the mulch away from the trunk?

Do you happen to know if these are eastern hemlocks, or Carolina? Eastern hemlocks are famous for shallow, aggressive root systems. Is it possible that the other plants in this area grew up with the hemlocks? That would be different from putting a new plant in a hole in the area where the hemlock roots are already established.

If I were you, I'd consider relocating the rhody - drastic, but if it was a big investment and it's on its way out, it might be your best bet at this point.

My guess is root competition from the Hemlocks. Those big trees will soak up all the water, probably most of the nutrients as well. Is the whole area mulched? Water the entire area with a sprinkler system, not just the Rhodie. Include the root zone of the Hemlock(s). The Hostas will love it and so will the Rhodie and the Hemlocks. If you don't get an inch of water through rainfall each week, then you should provide it. Don't stop after the summer heat. If the Fall is dry then make sure the Rhodie goes into winter fully watered.

Steve

This post was edited by steve_mass on Thu, Apr 11, 13 at 21:17