I think I have tobacco rattle virus on a peony. It is only on certain leaves. Do I need to destroy the entire plant? If so could I wait until after it blooms?
Thank you for contacting the Toronto Mater Gardeners with your concerns about your diseased peonys.
Unfortunately the tobacco rattle virus first gains a foothold in the roots of the plant , and if it is observed at all in the leaves, that means the whole plant is already infected and should be removed as soon as possible. It is important when you remove the diseased host that plant that you take care to sanitize your shovel or pruners that come in contact with the diseased plant or roots, so as not to spread the virus to any of your neighboring peonys or other many other susceptible species. Please refer to the following link which details what other plants you may want to keep an eye out for: https://pubs.cahnrs.wsu.edu/publications/pubs/fs284e/?p-page=1
To sanitize your equipment either wipe of surfaces with alchohol or dip in bleach.
It is also wise to not plant any of the susceptible species as a replacement plant, since the virus is likely present in the soil, or carried by nematodes who act as a vector.