If sprayed on the lawn where you are trying to get rid of the worms, you will also kill the grass. If that is not a concern, pour a bottle of highly acidic vinegar into an empty spray bottle and spray away; you may need to repeat this several times to kill all the worms.Click to see full answer. Similarly one may ask, how do you kill worms in soil?Harmful pests such as cutworms and leafminer larvae should be submerged in warm, soapy water to kill them so they don’t harm other plants. There are a range of insecticidal soaps that are effective at killing pests. Use a ready-to-use insecticidal soap and spray the worms, repeating the application as needed. what product kills earthworms? Currently, only one readily available insecticide is known to reduce and kill off earthworm populations. Sevin, a carbayl-based product, is intended for killing off grubs in a lawn but has been found to reduce earthworm populations as well when used at the recommended dosage amounts for grubs. Also know, does bleach kill earthworms? If you’re going to fish the same day you’re grabbing worms out of the yard – you can use a mild solution of diluted bleach – they’ll pop right out of their tiny little holes. However, you must rinse them off or they will die quickly.Is it OK to put earthworms in potted plants?Yes, it is not just OK, it is quite beneficial for potted plants to have a few earthworms in their soil. Earthworms never eat living stuff and majorly feed on decomposing bacteria only. The worms that feed on live roots are called Nematodes or Round Worms.