Answer: Hybrid roses are grafted onto vigorous root stocks. If the graft is damaged, the grafted top will die off but the vigorous root stock will grow and develop flowers. If you trace the stem with the red flowers down to the main stem of the rose you will find it is either coming from below the graft or from the roots themselves. The graft is a swollen area on the main stem of the rosebush. If you do not prune your roses to remove anything that emerges below the graft, or if the graft dies down in the winter because it was not protected from the cold, you will end up with growth and flowers from the root stock. With your Sunny Delight you may find that the grafted top died out completely. With your Aperitif, only some of the original stems have survive and the root stock is trying to take over. Prune off the red flowering stems, as far down as possible before the root stock overwhelms your hybrid rose.
Best wishes with your roses!
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