Hi everybody, Thanks very much for all of the feedback - much appreciated. Here's the follow-up: I was agreeing with the fungus theory (and the overfertilized theory), and then I took two leaves from this plant to my local garden center where I got a chance to show them to our local plant expert (sells houseplants and does a regular column in the newspaper). He looked at the leaves carefully and said that not only does this plant have scale but it has *spider mites* and he believes this is the crux of the problem. He diagnosed the spider mites by a slightly metallic sheen the leaves had when held up to the light. Also, there was a fair amount of honeydew on the leaves, which I thought was a product of the scale. He sold me some Bayer's Rose and Plant Insect Spray which I have dutifully sprayed all over the plant. I confess I'm feeling pretty guilty about this since I generally prefer organic means to work through things like this but the plant is in such distress I caved in and bought the spray. I'm going to give it a week and see what happens. I also intend, once it's had a few days to recover from the spraying, to replace all of the potting soil and thus eliminate the overfertilization variable. Thanks again for all of your suggestions. If any of you thinks that this solution seems mistaken, please feel free to respond. cheers, papercarver

The brown spots appear to be common hydrangea leaf spots, sometimes a fungal infection called Cercospora Leaf Spot. See here for more info: http://www.aces.edu/pubs/docs/A/ANR-1212/ANR-1212.pdf Most of the time, this is caused by overhead watering. If you do this, try watering the soil instead and do it very early in the mornings. Clean up plant debris that may contain spores, discard leaves in the Fall on the trash and, if you can afford it and the problem is bad enough in your opinion, replace the mulch too. You can also apply fungicides and the article mentions some of them but they can be $$ expensive so I just follow those suggestions when it comes to the ones that I too have with leaf spot. I am not sure about the loss of leaves. Sounds mysterious since you have not mentioned anything that would account for that. Normally, this would require something like not watering it (the rootball dries out for example), winter damage or applying insecticides or fungicides to the plant or to nearby plants. Leaf spot can make the plant loose some of these leaves as they first appear to have the lesions and sometimes the leafs brown out and fall. But usually the infestation is not THAT bad. If Bluebird lost the leaves in this way then you may want to spray after all as that is kind of a big thing in my opinion. I normally see this issue on mine by late August or in September so this is kind of early. And I just live with the problem until the plant goes dormant in December. Then I carefully cut the leaves off without touching the stems (invisible 2016 Spring flower buds will usually be near the end of the stems).

Danny Clark, I do not know the plant well enough to be specific; but the evidence (about 400 plants) suggests an intensive operation. It is easy for a fungus (my guess) to proliferate under such conditions. That you have had to cull 50 plants indicates an infection that has taken hold. My suggestion is to positively identify the causative organism; separate the remaining plants into 3 well defined areas. Space them adequately to facilitate air circulation. Classify them as "Good" "Going" and "Gone". Obtain a chemical (I cannot think of an alternative) which targets the pathogen/pest and,as a bonus, also lists the site (Boxwood) on the label. Apply to all three groups at the curative rate. Thereafter, apply at varying intervals to each group. The worst affected group can be treated at the shortest interval; and the "Good" group at the longest interval. Observe at weekly (at the very least) intervals; shift plants from one group to another as you see appropriate; and cull - ruthlessly! I wish you luck - sincerely! Because I know from experience, that you will need some of that also.

Photos of whole bush and close-ups of leaves and stems--are needed. Is it planted in at least 6 hours of sun? What has the weather been like? very hot, like 95 degrees to over 100 degrees for several weeks? Excessively rainy? overfed (like excessive nitrogen)? your garden zone or general region or state? Problems with Japanese Beetles? etc. How long ago were they planted in your garden? All sorts of factors might be involved--and could be a combination of things. My roses were looking rather pathetic by early August due to several factors, Japanese Beetles eating them up and a month of excessive heat sending them into a semi-dormant state being the major problems. Now, the Japanese Beetles have left and the temperatures have been mostly under 90 degrees, followed by a week of rainy weather--and my roses are putting out new leaves like crazy. Oh, yes, I also gave some of them their usual late-summer feeding which helped in the recovery--but avoid buying lots of products and piling them on the poor roses. Basically, Mother Nature (beetles, temperatures, water) will handle a lot of the problems. Knock Outs are considered disease "resistant"--but no rose is absolutely immune to disease, especially if the rose was not kept healthy before it got the disease. Keeping it healthy usually refers to giving it plenty of sunshine, feeding it regularly, and providing adequate (but not excessive) water regularly. If the roses are fairly new in your garden, it might be that the roots were damaged. Only time and adequate moisture will help in that recovery. Let us know more about your roses' growing conditions, and maybe we can help. Good luck. Kate