Perennials, shrubs and grasses getting spots and then die

Asked July 24, 2019, 3:24 PM EDT

Started with yellow spots on daylily leaves then whole plant became yellow and leaves soft. Moved to mums and yarrow which have died. English ivy has brown spots on leaves and half of plant is dead. Half of the Karl Forester grass is brown Neither of these plants got soft leaves before they died. Leaves turned brown.and then died. Disease has just showed up on a Hydranga shrub. Homeowner used Preen in front and back yard in Spring. Only front yard has disease. I'm an MG and would like a second opinion. My guess is it is some kind of virus.

Pennington County South Dakota

1 Response

Hello,
This is probably not a virus since so many different plants are affected. The first two photos look more like a bacteria spot for the first photo and bacterial rot for the second one. The third photo is a little harder to see, I would wonder about some major physical damage from wind or debris or if there was some inadvertent spray in that area. But again I can't see much in the picture as it isn't real clear, I would wonder what the rest of that plant looks like or if the damage is all in this one area. This has been a good year for the bacterial diseases. Even in the western side of the state has seen more rain fall than normal. These diseases like areas where there is poor air circulation, the extra humidity and dew in the mornings is conducive to the bacterial and fungal diseases.