I can't ID my rhododendron ailment. Help!

Hi there. I'm new here and need some help. There has been a rhododendron in the flower bed since before we moved in over 20 years ago. I vaguely remember a few white flowers many years ago, but haven't seen flowers in the past few years. I planted a hydrangea and an azalea about 4 feet away and they are doing great. The leaves of the rhododendron seem pretty green at most, a few do have some browning, but the main thing is that the buds get brown and any blossoms seem to be all dried up and brittle, with no actual petals! Any thoughts or suggestions would be great! Thank you!

I wonder if this is a cultural issue.
Are there salts or minerals in the water that plants do not like?
Are you deep soaking when you irrigate?
Are these plants mulched with some sort of organic matter?

Rhododendrons are forest floor plants with relatively shallow roots. They evolved with a LOT of leaf litter decomposing over the years, so they are used to rich, deep soil with very good drainage. Their roots are not as deep as most shrubs that thrive in full sun, so they do need irrigation more often to keep the soil damp, but they need the good drainage that lots of organic matter can provide. Occasional deeper irrigation to flush out any salts and minerals from the soil can really help.

If this is not the problem, it can still be part of the answer.

Rhodys can get several diseases, and other cultural problems like leaf burn in too much sun.

Thanks for the response, Diana_K

I really haven't done much to the existing plants that were here when we moved in. Just watering when I water my annuals. The rest I've pretty much left up to Mother Nature's schedule. There were a few weeds - one practically a small tree! - that we removed. I am wondering if plant food made for rhododendrons might help at all.

Annual flowers are shallow rooted, and demand frequent watering. It does not have to be very deep.

Rhododendrons have much deeper, wider spreading roots than annuals. Compared to annuals Rhodys need much deeper soaking, and more time between watering for oxygen to enter the soil.

If you are watering the Rhodys on the same schedule as annuals you are keeping the surface too wet, but not deep soaking the whole root area.

i believe that rhodies also are one of the few plants that actually drink water through their leaves. i read that somewhere. if you haven't had rain, a good washing with the hose could benefit them.

Most land plants take in water and fertilizers through the leaves. They have specialized cells and openings called stoma, that can open and close as needed.

You can fertilize many plants with foliar sprays of highly diluted fertilizer (1/10 the package recommendation) and the plants will take it in through the stoma.

hey diana,
well, of course that makes sense. lol i guess i should know better as i do foliar feed, etc. i think what threw me off course is that in my Southern Living Garden Book, out of the thousands of plants included, the section on Rhodies makes specific mention to watering the leaves as well as the roots. "because they absorb water through their foliage, wet both the leaves and root zone when you water". i guess i got confused and thought there was something different or special about this genus when it comes to watering and uptake of water through the leaves.

Plants that are native to foggy areas might be more efficient at taking in water that way. For example plants native to the Namib desert get almost all their water via leaf uptake of fog.
http://en.wikipedia.org/wiki/Welwitschia
And in the coastal redwood forests of California the plants depend on fog through the essentially dry summer for their water.

So there are specialists that really go in for this sort of thing. But the average garden plant can do this, too.