Your roses might not be dead; there could be live cane below the soil line, or at the soil line. I would prune off the dead wood, and see what happens this spring. I'm not familiar with Don Juan, but it might be prone to dieback in a cold zone.

Having been the victim of severe early spring freezes several years ago, my roses had to undergo an equally severe pruning to get rid of damaged canes. Definitely cut them back about an inch below the black part. But check and see if the center of the cut area is a nice healthy white. If not, cut back more until you come to that clear white center. That well could be back to the soil line in some cases. However, new growth will depend on the rose having a healthy root system. If the rose does not have good roots, I would start looking around for the reason--eaten off by critters? poor drainage? burned roots from multi-chemical fertilizers like Bayer (any of those all-in-one, 3-in-one, etc., products). Newly planted roses should not be fed until they have produced significant growth in their new spot. Since you have already potted the rose, I'd guess the best you can do now is prune as I indicated above, water regularly, and keep it in semi-shade for about a month. Maybe it can be babied back to health. Good luck, Kate

Buford, The one time I'll go in and cut lowest is when the cane is mushy. This hasn't happened often, and I don't know what the disease is, but sometimes the cane has leaves that don't look good, and I'll wiggle it to see if it's broken and it's not broken, it's mushy. Then I will cut lowest possible, usually in stages and I follow the cleanliness regime that Cass recommends (sometimes with adding bleach in between cuts to the secateurs if I think the disease has a real lethal potential.) The cleanliness that Cass talks about is so important. About rugosas: We visited a garden Wednesday where we'd watched two beds that were primarily Pink Grootendorsts with a few interplanted forsythia. One bed is gone, replaced with grass. In the eight years we've watched these, only one plant had gotten Rose Rosette, and we'd pruned the sick canes off; that bush is still RRD-free. But with no care, another plant is a RRD mess now and forsythia is taking over. The remaining five Pink G's are mostly dead canes. In my part of the world, have have seen this dead cane thing on rugosas in my yard, I try to cut them back as far as possible and it makes a better looking rose. But I've seen some mass plantings of rugosas up in the mountains (clear zone 6 cold) and many of the rugosas are mostly similar dead canes. Down here, the rugosas aren't 'no care'. The cause? Sometimes you'll see a swelling on the canes. I've sent some of those to some plant pathologists who couldn't find any boring insects or other pathogen. I'm afraid we may learn more about rugosa diseases as northern Europeans consider ways to fight and kill rugosas which are becoming known in parts of Scandanavia as invasive alien species.

Read your post. Sounds like a classic case of overwatering. I have bamboo in South Texas (zone 10). I started out overwatering as well. Bamboo does not like to be soaked. If you can, dig down a little ways and look at the node (culm lines). You can visibly see a drowning plant. All of the tissue will be mushy and brown around the node. You need to let this dry out to try to get some new growth and root, but do not leave it exposed to air after you view it. Cut back your watering drastically. If you see the leaves start to curl in, then you will know it is too dry and time to water again. As to fertilizer - ABSOLUTELY. Bamboo is a grass and so LOVES a very high nitrogen count fertilizer. You can feed it monthly (or less with a slow release fertilizer). You can buy a very inexpensive grass fertilizer like a 32-0-10 or 29-0-0 at Lowes or Home Depot. Make sure it is NOT a weed and feed variety or you can kill the plant. The Scotts sells for $35 for a 50 lb. bag or $13 for a smaller bag. For my full grown, 5-foot diameter plants, I put a full coffee cup per plant. If your Alphonse Karr plant is new and about a 5 gallon size, I would put 1/4 to 1/2 coffee cup of the fertilizer spread all around the plant, not just directly on the roots, and maybe a little more after you see it start to respond. Water a little to soak it in and then watch the leaves turn brilliant green over the next couple weeks. If you have a high alkaline soil, you can also add a few minerals like Calcium and Magnesium, or just some garden sulpher. That's why I buy the grass fertilizer with added 2% sulpher. If it looks like you are going to lose the plant, I would dig it up and let it recover in a mix of 1 part sand, 1 part peat moss and 1/4 part compost until it starts to shoot again. Remember, it likes full sun 5-6 hours a day. Good luck. Alphonse is a beautiful peach-shooting plant!