By Dan Gill
LSU AgCenter Horticulturist
(02/24/17) The fact that many of the plants that we grow as ornamentals are considered poisonous is a topic that horticulturists don’t often discuss. After all, cases of people eating poisonous plants are relatively rare, and there is no need to cause the public undue alarm. However, there is a need for people – particularly those with children and pets – to be aware that poisonous plants exist in our landscapes and inside our homes and be aware of how to deal with them.
A surprising number of indoor and outdoor ornamental plants are considered poisonous. Indoor plants such as dieffenbachia, Chinese evergreen, pothos ivy, English ivy, florist azaleas and philodendrons are common in many homes. In the landscape, popular plants such as amaryllis, angel’s trumpet, azalea, caladium, elephant ear, irises, lantana, oleander, privet, sedum, wisteria and yellow jessamine possess at least one poisonous part. These are just a few examples.
Here are some safety measures to prevent problems with poisonous plants:
– Never leave young children unsupervised outdoors. Be especially careful when children are around colorful flowers, berries or mushrooms.
– As soon as they are able to understand, teach children to never, under any circumstances, chew on or eat any part of indoor plants, plants in the landscape or wild plants. Teach children to recognize poison ivy and stay away from coming into contact with it.
– Don’t make medical preparations from plants for yourself and, particularly, never for your children.
– Don’t believe old sayings about eating unknown plants if you get lost in the woods. What birds and other animals eat is not necessarily harmless to people. There is no safe, simple test for poisonous plants. Cooking does not always destroy the poison.
– Don’t grow poisonous houseplants if you have young children, or at least make sure they are not accessible. It would be better to stick to nontoxic indoor plants.
– Always store seeds and bulbs for your garden in a safe, inaccessible place where young children cannot find them.
– Don’t eat unusual parts of familiar edible plants. While the tubers of potatoes and the fruit of eggplants, tomatoes and peppers are edible, the foliage and green tissues contain toxic alkaloids that may make you sick if consumed in sufficient quantities.
In case of poisoning or suspected poisoning, call your family physician immediately and be prepared to tell him or her the name of the plant eaten. Or take the patient along with a piece of the plant eaten to the emergency room of the nearest hospital.
Most adult poisonings involve the eating of wild mushrooms, and most cases among children involve the very young. Common sense, caution and educating children are the best ways of preventing problems with poisonous plants.
Pets are at risk, too
Most animal poisonings by plants involve livestock such as cows and horses. Any veterinarian will tell you that poisonous plants are potentially harmful to pets as well, although most pet poisonings occur because of pets ingesting human medications. Puppies and kittens, in particular, are bad about chewing on plants. Adult dogs that are home alone most of the day and get bored may also chew on plants. Cats are curious and will chew on a variety of plants, almost as if just to see what they taste like. You should not grow poisonous plants indoors if you have dogs or cats that might eat them.
Because pets cannot be taught which plants are poisonous, keep them away from poisonous plants particularly those indoors. Contact your veterinarian immediately if you suspect your pet has eaten a plant or plant part whether you know it is poisonous or not. Usually time is very critical.
I’ve encountered a number of instances where dogs have eaten the seeds of female sago palms (Cycas revoluta) and almost died or died as a result. This plant likely causes many dog poisonings in Louisiana. Dog owners, or anyone with dogs in the area, should remove the developing seeds now (January is better) to prevent dogs from eating them. Sago palms appear on the ASPCA’s top ten list of plants poisonous to pets, along with lilies (particularly for cats), tulip and narcissus, azaleas and rhododendrons, oleander, castor bean, cyclamen, kalanchoe and marijuana.
For more information
The Louisiana Drug and Poison Information Center is located at the University of Louisiana Monroe School of Pharmacy. The emergency phone number is 800-222-1222. You can find extensive information on poisonous plants on the Internet using a search engine. You can find lists of common poisonous available, or you can do an Internet search to find the poisonous properties, if any, of a particular plant.
For pets, the American Society for the Prevention of Cruelty to Animals has an excellent website for information at www.aspca.org. You can type “poisonous plants” in the search box to find lists of common toxic plants and nontoxic plants.
Angel trumpet. Photo by Tom Pope
Lantana. Photo by Allen Owings/LSU AgCenter
Amaryllis. Photo by Dan Gill/LSU AgCenter