Rosette Rose Disease is a serious disease that is infecting rose plants. It’s a viral disease that I’ve seen in Towns and Union counties. It can spread rapidly and kill rose plants within a couple of year of infection. Let’s talk about rosette rose disease, how to spot it, and what you can do about it.
Rosette rose disease was first found in California and Wyoming back in 1941. Since then it has spread towards the east. Rosette rose disease also infects wild roses. This is most likely the way that the disease travels. It can infect all roses and is particularly lethal to multiflora roses, which are a species of wild roses.
Mites primarily carry the disease. The eriophyid mite will feed on an infected rose. That mite will then move to an uninfected rose and pass the pathogen onto the new rose plant. Once a rose plant is infected, the pathogen travels throughout the plant. The mites will often feed on new growth of buds, stems, and leaf petioles. These mites are so small that they’re not visible to the naked eye. They ride on the wind to spread from plant to plant. It’s also possible for humans to vector the disease through grafting and pruning with tools that have the virus on them. Therefore, if you are pruning roses it’s a good practice to clean your tools with alcohol between plants.
The symptoms of rosette rose disease are usually quite clear. The shoots and foliage will have an unusual red color; the stems will look thick and succulent with long shoots. There will also be an overabundance of small, pliable thorns on the stems. New growth on the plant may have a witches broom appearance, meaning it has many branches close together.
Rosette rose disease only affects roses. However, it is a viral disease, meaning that if your rose bushes get it, they can’t be cured. There are no resistant varieties available on the market. There are some that are in research trials, so hopefully within a few years those will be commercially available. Since there is no cure let’s talk about how you can prevent your roses from contracting the disease.
The best place to start is by planting disease free material. Avoid buying plants that already look stressed and might be showing symptoms of the disease. When planting the roses leave space between plants so that the leaves and stems aren’t overlapping. This will make it a bit more difficult for the mites to travel between plants. Finally, if possible, remove wild roses from within 100 yards of your roses. This is not always feasible, but removing wild roses will decrease the chances of the disease being able to spread to your roses.
If your roses are already showing symptoms, the best course of action is to remove them. Infected plants will spread the disease to other nearby roses. The disease infects all the way down to the roots, so removing the roots is necessary to remove the virus. Bag up and dispose of all the plant material that you pull out. It’s not recommended to replant roses immediately into an area that’s been infected.
If you have questions about rosette rose disease contact your county Extension Office or email me at the address below. On July 25, the Union County Extension is putting on a Well Water Program. It will be at 5:30 in the Union County Civic Center. If you would like to attend, please RSVP with Union County Extension Office at 706-439-6030 or email me at [email protected].