Proliferation of Odd Flowers on Roses

Question from Sally:
My husband Brandon follows your month by month book for his roses but what happened to this yellow rose? All flowers have funny green buds in center. What could be causing that and what is it? Check out the picture of the Disneyland rose there must be a hundred buds in the middle of the flower.

Answer from Pat:
The condition that causes many buds to form in the center of a flower is a rare condition called “Bud Proliferation” or sometimes just “Proliferation” of rose blooms. Thank you for sending the photograph. Proliferation doesn’t often happen in home gardens. It was first noticed in nursery flower fields in Holland about twenty years ago and now has come to America where it is a problem for the growers of cut flowers. It did also happen back in the 18th century since we have written records of it.

No one knows what causes proliferation, but it most likely is caused by unusual weather conditions, swings in temperature and less sun than usual. Extreme changes of temperature or some kind of climactic causes apparently make the apical bud go wild and keep on growing many buds instead of making just one bud. Who knows? Perhaps it is caused by the amount of carbon dioxide in the atmosphere or a change in the amount. Another possibility is that it is caused by a disease but that is less likely.

Proliferation occurs more with some varieties of rose than with others, but once a rose has begun to do this it usually continues for a few years on that particular plant, and then when the plant is mature it will stop and make normal flowers again.

Proliferation does not harm the plant. If you don’t like the look of the flowers cut them back to the next 5-leaflet leaf and then the new shoot will grow and flower and it will be normal. So in some ways proliferation is similar to blind shoots and the solution is the same: cut it back and it will then bloom properly.