Fungus/virus hosta infection

Asked June 8, 2018, 8:24 PM EDT

I have massive numbers of plants (hostas, iris, lilies, phlox) infected with some type of fungus. It became apparent last summer and I started cutting back, spraying and using systemic products. I cut all foliage in my gardens back before winter and started the systemic and spraying again in the spring as well as fertilizing. I realize I will have to do this for several years but my question is when spots start appearing I have been removing the affected leaves but would it be better to just cut the entire plant back right away and continue to treat? Also how do I effectively dispose of the foliage without spreading disease further? I have been bagging them up then covering with a tarp and hoping the heat will kill it eventually but due to large numbers, they are taking up too much space. Help!

Otter Tail County Minnesota fungus hostas

5 Responses

We recommend bagging affected material and placing in the trash, however, with this large amount it may be better to lit it dry an then burn it. I don't think bagging and tarp will kill it since the temperature won't get high enough.

If I burn it, won't that spread through the air and spread the disease?

No, burning will destroy the fungus, however, hydrocarbons may be released as in the smoke.

Ok, good, thank you. So it is ok to let the removed plants lay out to dry without it effecting surrounding plants?

I would be concerned that if you air-dried the affected material near your other plants, it could contribute to the spread of the fungus to them. I would still opt for bagging things up tightly and putting it in the trash.

You may find some other hints here:
https://www.rhs.org.uk/advice/profile?PID=612