Roses are not poisonous to cats. Roses are a non-toxic flowering plant; their petals and leaves do not contain toxins harmful to cats. However, some cats like to play with flowers and plants when they are bored, and sometimes they may ingest some, which could cause poisoning.
Plants that are toxic to cats include: tulips, lilies, aloe vera, pothos, daffodils, ivy, azaleas, etc. Before planting plants at home, you should check whether they are toxic to cats.
