OK, so it's the one on the corner. That one would definitely get more wind exposure. It will also get more sun because it gets exposure from both sides of the house. How close is that bush around the corner and what is it? Have you seen blooms on all three and do they match? If so all I can think is that it is just a weaker plant. Sometimes that happens. You just get a weaker plant or graft and it never preforms up to snuff. Of it could just take longer to settle in and mature and then take off. All roses are not created equal.
