Answer: This is an interesting question. Since it seems healthy and your other roses are fine, I assume you must be taking good care of your roses. Without seeing the plant it is hard to say, but if it is a shrub rose or climbing rose for example and you have been pruning it like a hybrid tea rose, perhaps it is related to that. (The old fashioned roses bloom on old wood and would not need a hard pruning in early spring the way one would handle a hybrid tea rose.) Or, perhaps it is in less direct sun than your other roses. In less than six hours of direct sun including the hour of noon, many roses will bloom less or not at all. I hope this helps you trouble shoot.
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