|I sure hope you can help me. I have 8 Knock out roses. 4 of them are 4 yrs old. Until this yr have been beautiful. I did the same thing last fall getting ready for winter and in the early spring I feed them with Bayer fertilizer for roses. I have done this for 4 yrs and they have always looked great. This yr however they look like they are on thier last leg. They have little to no new growth. I have also discovered we have grubs. I have just treated my landscaping with Bayer to get rid of them. What do I do to save my roses?? Should I dig them up and move to another location that doesn't seem to have the same issue with grubs? Can all the damage be the result of grubs?
|Grubs are a problem with turf grass (feeding on grass roots usually in mid to late summer) but would not be affecting your rose roots. So I suspect something else is happening to the roses. They might have been stressed by oscillating temperatures this past spring. Or, they might have suffered root damage from voles during the winter. Or, they might have suffered accidental herbicide or other chemical damage. Without knowing more of the symptoms it is difficult to guess what the cause would be.
At this point I would suggest top dressing with a good quality compost, trim off any winter damage, keep the soil evenly moist (damp like a wrung out sponge, not sopping wet and not dried out) and see if they come out of it.
In the meantime, you could also consult with your local county extension and see if they have any suggestions as to what is happening to the roses. I am sorry you are having trouble with them.