Outdoor Plants That Are Poisonous to Pets

For wandering outdoor pets there are many dangers. Many gardeners and those sprucing up their landscape are aware that there are poisonous plants. Toxic plants can not only make your pet sick, they could be lethal. Check before any planting to see if your choices are part of the list of plants that are poisonous to pets.


The larkspur (Consolida ajacis) is from the buttercup family and part of 40 species of Consolida. It is an annual plant that is easy to grow and a hummingbird attractor. Flowers are on 2- to 3-foot spikes in blue, white, pink and lilac. They are typically chosen for beds and borders. In humans, foliage can give a contact rash. For pets, the seeds are poisonous. Leaves and flowers can cause stomach problems if eaten, and the foliage is toxic to cattle.

Autumn Crocus

The autumn crocus (Colchicum autumnale) is from the lily family and has 45 species of plants. It is a perennial with purple, pink, or white glass-shaped flowers 5 to 7 inches tall. It is used as a meadow garden or as color through a ground cover planting. All parts of this plant may cause skin irritation if touched and be toxic if eaten.


The jimsonweed (Datura stramonium) is from the nightshade family and is an easy-growing annual. There are trumpet-shaped purple flowers, and the plant gets 3 to 4 feet tall. It is a foul-smelling plant with sweet-smelling flowers. It is typically used in dried flower arrangements and used in Europe for the hyoscyamine alkaloidal drug. All the parts of jimsonweed are poisonous. Children can be poisoned by the flower nectar, and cattle have died eating it. Skin rashes can come from the sap. Smelling the flowers often gives headaches.

Cut Leaf Philodendron

The cut leaf philodendron is a fast-growing evergreen perennial that is part of 200 cultivars of philodendron. It has glossy leaves up to 3 feet long and purple-red spathe with tiny flowers. It can get 15 feet tall. It is used as a popular container plant in offices but can be used outdoors as well. Sap from a philodendron can cause skin irritation and the plant is poisonous if ingested.

Castor Bean

The castor bean plant (Ricinus communis) is a fast-growing evergreen annual that gets up to 40 feet tall and 15 feet wide. It has glossy purple or red-green leaves 12 to 30 inches wide and greenish yellow flowers on 8- to 18-inch tall spikes. It is used as to have a tropical garden feel. The castor bean plant contains the most poisonous of the naturally occurring chemicals. All parts are poisonous. The seeds are highly toxic. It should never been used around children or pets.

Keywords: poisonous plants, toxic plants, plants that are poisonous to pets

About this Author

Tina Samuels has been a full-time freelance writer for more than 10 years, concentrating on health and gardening topics, and a writer for 20 years. She has written for "Arthritis Today," "Alabama Living," and "Mature Years," as well as online content. She has one book, “A Georgia Native Plant Guide,” offered through Mercer University; others are in development.