RECIPE: Kill Poison Ivy Plants 3 cups vinegar 1/2 cup salt 1 tablespoon liquid detergent or soap I sprayed this using a pump up sprayer that I bought for 10 bucks and the next day I could see that the solution was working. Apparently, the salt kills the poison ivy, and the dish soap helps the mixture stick to the leaves.
How To Kill Poison Ivy and Remove It As Well As Prevent Regrowth - Dead plants and vines can still cause an allergic reaction up to two years later. The roots of the plant are over 1,000 times more toxic than the leaves and vine. The entire poison ivy plant is toxic.