Hosta disease diagonsing

Asked May 23, 2016, 1:34 PM EDT

I have hostas that have been established in a home for 20 years. No moving, no transplanting, no digging or working of any kind in this established hosta garden. This year leaves are showing brown spots, turning yellow, etc. It looks like Hosta Virus X. From what I've read, that is caught through infected tools, but I assure you none of my hostas have been touched. These symptoms started showing up before the frost so early May sometime. Is there a way to treat this or are they infected indefinitely. Also, if I have to pull up all these hostas, is this disease in the soil for future plants. Thank you so much for all of your help. ALSO, how do you treat black knot in a crabapple treat caught reasonable early?

Sherburne County Minnesota hostas horticulture hosta diseases

1 Response

This doesn't look like the virus, but you may have to bring a sample into our diagnostic clinic to be sure. http://pdc.umn.edu/

Here is some additional information:
http://www.americanhostasociety.org/Publications/41/HVXarticle.htm

You didn't ask in your message but the two additional photos seem to be Black Knot disease. These branches should be pruned out and destroyed. Here is some more information:
http://www.extension.umn.edu/garden/yard-garden/trees-shrubs/black-knot/