Mine is a profuse bloomer now that it's headed toward four years in the ground. It hasn't been fertilized since I planted it. It sure puts on a lot of growth. I can't imagine what it would be like if I fertilized it. Since what you're doing isn't working, I can think of a couple of things to try. First, stop fertilizing it or more specifically, fertilize it for growth now with something short-acting. Maybe your fertilizer program is promoting growth in the spring when it should be flowering. Mine seems to leaf out and flowers without putting on much growth. After flowering, it grows like a house afire. Alternatively, think about pruning it this summer. I don't think I'd shorten canes. I'd think about reducing the overall amount of wood, remove basals. See if you can get the rose working on the best, newest wood. There is a risk -- pruning might stimulate a bunch of new growth. I wouldn't try both things at once. I'd try no fertilizer or limited, short-acting fertilizer first.

In colder zones I think it is better to let the leaves be until they fall naturally. The energy from the photosynthesis is stored in the leaves and the substances from the leaves are absorbed to the canes before they let go of the leaves. A lot of the new growth comes from this energy stored in the canes in the spring (One of the reasons I wait to reduce the sizes of my rosebushes until they have lost their leaves or before a heavy snowfall ..not pruning, I wait for that until spring, but just reducing some of the long canes so they won´t break under the weight of snow/Ice storms). Some roses cling more to their leaves than others; Madame Isaac Pereire and Constance Spry only looses about half their leaves before the spring when they finally let go of them when the new growth begins. The only leaves I remove now (If they don't fall of by themselves), are those that I can see have spot/fungal diseases. I want as few fungal spores as possible to survive. It is common sense and good garden hygiene to do this, and may help reduce spraying next season.

Here's a little update on my pumpkin growing adventure. After a few days of non-growth the boys are back on track. Spike has taken over the lead in the growth department. Stats: Circ. 44' OTT 30' & 30.5' 104.5 OTT= 32# weight. Not earth shattering, but for a twenty-day old pumpkin, not too shabby. The others, Pancho and Lefty are a little behind. The image shows Spike with some of the foliage pruned away. In the foreground are giant sunflowers, about 9' tall now with no heads yet. I have switched to foliar feeding every other day using 'Monty's Joy Juice' (yep that's the name.) I couldn't find the Neptunes Harvest. Monty's seems to be working pretty good as well. It is a late season feed that comes in at 2-2-15. I also blend in a little molasses for added calcium and micronutrients. Here is a link that might be useful: Monty's Joy Juice

It does look like nutrient deficiencies, which have the twin benefits of being slow and correctable. The interveinal yellowing, where the veins stay green, is more likely magnesium than iron... but the real way to tell is where it's happening. Magnesium starts at the bottom, iron starts at the top. The pictures make me guess it's the former; you could mix up a tablespoon or so of epsom salts in a spray bottle and spritz down the plants, and see whether the leaves color up again. The yellow leaves probably are nitrogen, and a light foliar feed is very unlikely to give them too much nitrogen. Spray them down with fish emulsion and see if they green up. If they do, start giving them light doses of nitrogen regularly. Clay soil can be very rich in just about everything... except nitrogen; your amendments weren't with anything that would boost that N level for any length of time, particularly if the chicken manure was old. Best of luck -- the plants should be fine once you can give them what they need. --Alison