Question
I have a yellow rose bush,among the yellow roses has appeared a white rose. Is this normal?

Answer
Roses have bloodlines just like humans and there are many different types roses that go into making a modern rose. Sometimes one of the roses in the background is strong enough to break through and you get a different coloured bloom on the bush. Breeders then would take that white rose, propagate it and make a new white rose bush. There are other reasons why a flower turns a different colour such as hot weather conditions, soil make up, fertilizer etc but usually most of the flowers on the bush are discoloured. Hope this helps. Lynnette