Answer: Ants typically go where food is available so I think your mini-roses might be hosting some aphids. Aphids excrete a sticky substance called honeydew, which ants love. They love it so much in fact that they will 'herd' aphids, keep them groomed and out of harm's way so the aphids will continue to feed and produce honeydew. Once you get rid of the aphids (Insecticidal soap works), then the ants will go away, as well.
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