Bluesgarden, if you notice some tiny spots on the petals that get larger and larger prior to wilting, you may have a fungal infection called Petal Blight. Blossoms should be disposed in the trash and you may consider replacing the mulch & cleaning any plant debris after the blooming season is over. Then maintain clean practices as often as possible. Water the soil (not the leaves/shrub) early in the morning. Avoid keeping the soil wet. Below is a link with more information. Here is a link that might be useful: Petal Blight Information from the ARS

Root rot is fatal. What you do with the leaves won't matter. Plants wilt and die slowly when their roots become blocked. There are two causes of this: Root strangulation. This is best prevented by proper root pruning when planting. If the plant is not too far gone, it might be rescued by digging and removing the soil. Then cutting any circling roots that may be strangling other roots. The roots need to be opened up. On larger plants, some of the top must be removed to compensate for the weak state of the roots. Any time the roots are exposed, they must be kept moistened. Roots that dry out will die. Phytophthora crown rot or wilt. This root rot is the major killer of rhododendrons and azaleas. It develops when roots are growing in wet conditions. The rot is more prevalent in warm summer conditions. Plants infected with crown rot caused by the fungi Phytophthora have roots which become clogged with brown fungi internally. The roots get blocked and the plant wilts and dies. There is not much of any cure for crown rot. Some varieties of rhododendrons are vulnerable (Chionoides, Catawbiense Album, Nova Zembla) and some are resistant (Roseum Elegans, Scintillation, PJM). Sphagnum moss and bark dust combined with good drainage seem to prevent crown rot, but do not cure it. Wilt and slow death can also be caused by juglone poisoning from black walnut or butternut trees. Plants wilt and die suddenly is usually caused by roots which are girdled by larvae of the Black Vine Weevil or Strawberry Root Weevil. Adult weevils feed on the leaves at night. Specimens may be collected at night for identification. The major damage is caused by weevil larvae which girdle the roots and kill the plant. Larvacidal drenches may be used to kill them but are of limited effectiveness. Foliar sprays are very effective at controlling adult weevils when leaf notching starts. Foliar sprays must be repeated until no adults emerge. Entire portions of a plant die if a borer is in a branch. Borers only affect the portion of the plant away from the roots from the borer. If the borer is in the main trunk, then the entire plant will wilt and die. The plant can be save by cutting off the area with the borer and letting the plant regenerate from the roots.

"Unfortunately, My Jane (I have three in different locations) is acting the same way in my garden, which was one of Hank's favorite yellows. " I'm still having good luck with 'My Jane'. In fact I had one that was in too low a spot and showing some dieback. I moved it on to the top of a mound of soil and cut away the dead bits. I experimentally did _not_ give it antifungal treatment, since I already have another My Jane in a totally different part of the garden that is fine. Well, that plant recovered very well. Just with the re-siting. So I would say for a yellow it is very tough. It's a better yellow than Capistrano, but only by a little bit. OTOH Jenny Tabol is a notch more saturated, and though some wouldn't like the pinkish edges, I think they help bring out the color. OTOOH, (on the other other hand...) Nancy Evans is WAY more saturated. But I protected my NE with antifungals for 2 years. It was planted on a mound. It is a gorgeous plant in and out of bloom, because the foliage is really nice too. When I stopped treatments, it quickly died. So its root rot resistance in a climate with nights warmer than 60F is virtually nil. One more good one is 'Yates Treena'. To me, slightly better than 'My Jane' but again nowhere near as good as Nancy Evans. So far so good with the root rot resistance. In fact the plant is so vigorous it worries me a little bit, because Capistrano was very vigorous before dying too. Also many of my rhodies are crowded and it will have to be moved soon, which will stress it a bit but give me a chance to reset any circling roots if those are a problem. If I had known in 2006 that I would have been so captivated by rhodies, I would have immediately started planting more high shade. Alas it took about 4-5 years before I realized I had a rhododendron problem haha.

Okay, so one of the euphorbias I got at the C&S show last week is starting to put out flowers and some new growth, and the potting medium was dry, so I lightly watered it. Anyway, this actually leads me to another point. I remember reading a few sites suggesting that you use a small amount of topsoil instead of a small amount of peat in cacti and succulent potting mix because it tends to be fairly loamy and a lot easier to re-wet than peat, which I tend to believe because peat is terrible to re-wet. However, I kind of assumed that topsoil would be too heavy for most container plants. Then again, if it's in a fairly small amount in proportion to perlite/pumice/bark and the soil is still relatively airy and fast draining, maybe not. What made me think of this again is that, when I watered the euphorbia in question, the moistened soil DID have a distinctly topsoilish smell to it, and the mix the C&S society guys have their stuff potted in seems to be fairly fast draining. Also, C&S Society, so I figured they'd know their stuff. I think you also mentioned adding clay into the mix earlier (though I'm not sure if you meant clay-based soil or clay chips/balls). Anyway, a (small) amount of topsoil seems like it could work for this, although, as I said, I'd be concerned that it'd still potential be heavy or prone to caking. Any thoughts on that?