Growths on Your Roses
My old-fashioned roses have growths on their stems and roots. I think they're called galls. Is there anything that can be used to kill this disease? I have cut out the damaged stems and roots, but it continues to spread.
—Mae Adams, Suring, Wisconsin
Lumps and strange growths are often called galls. Most are growths plants produce in response to an insect feeding on it and require no control. In this case, the galls have been caused by a bacteria that's invaded the plant.
Continue to remove the galls by pruning several inches below the gall into healthy tissue. When you do this, be sure to disinfect your tools with bleach or alcohol between cuts. This keeps the problem from spreading.
A more severe solution is to completely remove the plant and wait several years before planting another rose or plant susceptible to galls in its location.