My hybiscus plants were planted in a flower bed that had been exposed to motor oil in the past.?

They were beautiful at first but now leaves are turning yellow and plants are withering. How do I save these plants.



I had dug out all the dirt I thought was exposed, and changed with new dirt.

My hybiscus plants were planted in a flower bed that had been exposed to motor oil in the past.?
You probably couldn't have dug out all the motor-oil-polluted dirt, since it seeps into everything. The proof is that it sounds like your plants are dead. You could pull them out and put them somewhere else or put them in pots with potting soil if they're not too big, but it sounds like it might be too late.



Don't plant anything in that location again. Pave it over or something.