I’ve accidentally poured petrol on a rose bush what can I do to save it?
Lightly dig around the bush and remove the soils down about 4 inches in depth, water well with a product called super thrive in the water. Fill in removed soils with a good bagged garden soil and compost mix. The soils removal will hopefully remove remaining residual contaminants before they travel any further. The feeder roots are likely burned, so destroying some while removing the soils is not likely to harm much. The super thrive product helps the bush to overcome shocks of all kinds and will hopefully offset the poisoning that the roots have taken in. The new soils with compost will create as good a situation as we can hope for in helping the feeder roots to re-generate. If you have any buds or blooms on the rosebush right now, cut them all off. I know that is hard to do but it will allow the bush to focus on survival rather than bloom production at this time.