Kalanchoe are self-sufficient plants, but they do benefit from occasional fertilizing. You can use a well-balanced fertilizer such as 20-20-20. Read the instructions on the label carefully before applying. Do not over-fertilize the plant.
Kalanchoe does belong to a group of plants that contain cardiac toxins (bufadienolides). However, ingestion by dogs and cats most often results in gastrointestinal irritation or upset.