To stop your artificial grass from smelling, look for any unwanted source of the smell in it. If you have a pet, look for feces or urine smell around the lawn. Remove it as quickly as possible. You can use a re-odorizer or simply use soap and water on the affected area to remove the smell. You can use vinegar to remove the odor. It works as a disinfectant on the spot and eliminates the odor immediately.