I work in a garden center. I am certified professional in my trade with many years experience.
I had a couple bring me some cuttings off of their rose bushes that were showing twisted distorted leaves. It looked to me like classic herbicide damage and I told them so.
They tell me:
“We don’t use weed killers, it can’t be that! ”
Me: “Are your roses near a lawn where Weed ‘n’ Feed was used?”
The wife: “No, we garden totally organically. No weed killers!”
Me: “Hmmm. Are the roses near your neighbor’s yard? Perhaps they were spraying for weeds and some drifted onto your roses? ”
They said no, the roses were nowhere near the neighbors.
I questioned them a bit more and reiterated that it really looked like the kind of damage you get from a Roundup type weed killer. The wife repeated that “No way” would they have used any weed killers.
“We would never use that! We are organic gardeners! ”
The only other options I could come up with would be some kind of virus, or stress. I made a few suggestions that might improve the health of their roses, and off they went.
An hour later I get a phone call from the wife:
“Hi CappuccinoBreve, I’m calling to apologize. My husband confessed in the car on the way home that he’s been using Roundup without telling me! You were right and he is in so much trouble! ”