While it is difficult to speculate on why your dog is tearing up these plants and not others, Kym, we can tell you that Hibiscus species can be potentially toxic, possibly causing significant gastrointestinal upset that could lead to dehydration. Drooling, loss of appetite and depression are also possible. Typically, these effects are seen in cases of single exposures to a significant amount of the plant material, rather than the chronic ingestion of small amounts. However, due to its toxic potential, we advise keeping hibiscus out of your dog’s reach.