VIRUS MOSAIC

Identification

Many roses across Australia may have the appearance of these examples or other variations. Two versions exist with Prunus Necrotic Ringspot and Apple Necrotic Ringspot the official names.

Control

Caused by either infected propagation material or rootstock there is nothing that can be done if your plant shows this. Another name for this problem is ‘Heat Induced Chlorosis’ for the effect is more prevalent in the heat of summer or in hot weather.

Although the plant will always have this look it is in the cellular level of the plant and can only affect other plants in the propagation process. Cutting flowers, pruning or insects will not move it to other plants.

Most good nurseries now use a Virus Tested Understock for their rootstock and new varieties are unlikely to have the virus however old favourites and many Heritage Roses do not have ‘clean’ plants so it is just something that must be endured if wanting these varieties.

Research has identified ways to lessen the effect however the large cost eliminates rarer varieties from being cleaned up.