Dieffenbachia spp. Is a fast-growing plant that loves bright indirect light, and high humidity. Misting the leaves can be useful to maintain humidity levels. While it loves high humidity, take care not to overwater, letting the top 2 inches of soil dry out between waterings. Be cautious when caring for the Dumb Cane plant, it contains a toxic sap that can cause speech problems and swelling in humans. This plant is also toxic to both dogs and cats.