Witch's broom, or rosette, is a disease that can kill any type of rose within two years, although hybrid teas seem more resistant to the disease. Unfortunately, there is no cure for witch's broom, which some experts believe is spread by a microscopic mite called Phyllocoptes fructiphilus. The best gardeners can do is destroy affected plants so they won't infect others.
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Check roses for rapid stem elongation, thickened stems with more thorns than usual and short, deformed shoots with tiny misshapen leaves. It is these leaves that give the appearance of a witch's broom. If any of these symptoms are present, your rose or roses likely have witch's broom and will have to be removed.
Pull out affected roses, including roots.
Remove soil around affected roses, since it could contain mites that spread the disease. Discard affected soil
Burn or otherwise discard affected roses in a way that will not contaminate other plants.