Remedy

How to control shiny geranium, from WA noxious weed control board: Individual plants and small infestations can easily be controlled by carefully hand-pulling, bagging, and putting in the trash. Make sure to remove its fibrous roots to prevent resprouting. Larger populations can be covered with sheet mulch - ideally overlapping pieces of cardboard covered with a thick layer of woodchips. Make sure to repeatedly monitor and control seedlings before they set seed.