Gardening Advice: Harmful Plants


Gardening Advice: Harmful Plants

October 3, 2001

Q: Our two young cats have taken to nibbling our houseplants. I’m afraid our baby may follow suit once she starts to crawl. I don’t want to give up my lush indoor display, but I’m worried about poisoning my child and pets. Any solutions? Meg Barnett Sanguinetti, Oxford, Miss.

A: Your best defense is to avoid growing any potentially harmful plants. That’s not easy, though, as many of the most common houseplants have poisonous properties. The ubiquitous arum family, for example, includes many species that contain calcium oxalate crystals, which, when ingested, cause burning and swelling of the tongue, mouth, and throat. In rare instances, the swelling may be severe enough to cause suffocation. Among the arums, look out for monstera, dieffenbachia, caladium, pothos, spathiphyllum, elephant ear, calla lily, and philodendron (the most commonly ingested houseplant). The sap of euphorbias such as crown of thorns, candelabra cactus, and poinsettia are caustic. Though not as dangerous as reputed, nibbling a poinsettia leaf can nevertheless make a child nauseous. Flowering plants that make their way into the house as seasonal accents or gifts can also spell trouble. I don’t want to be an alarmist, but two of the most deadly beauties are oleander and gloriosa lily — a mere leaf of oleander can kill a child. Azalea, croton, datura, and hydrangea are toxic to a lesser degree. All parts (but especially the bulbs) of daffodil, amaryllis, and hyacinth are poisonous.     

In some cases, it’s the fruit that should be forbidden. Asparagus fern and bird-of-paradise are safe as far as leaf and flower go, but the fruits and seeds are dangerous. Be extra careful when it comes to plants with showy, enticing fruit. If eaten in quantity, holly berries and the fruit of Jerusalem cherry can cause nausea, vomiting, and possibly death. Mistletoe berries, though not as poisonous, may cause gastric distress. If you’re not willing to limit your selection so drastically, you can isolate plants from the grazers. Most of my indoor plants live in a sunroom separated from the rest of the house by a screen door. A hook latch high on the door keeps my toddler, and pets, from sampling the greenery. My older daughter, at 3 1/2, has had the dangers of eating poisonous plants drummed into her for so long that she is trustworthy alone among the plants. I can’t stress enough the importance of teaching your children about the danger. Even if you rid your home of all suspect greenery, there are many dangerous plants in the garden and the natural landscape. Kids need to know that they must not eat any part of a plant without first asking. If a crisis arises, call your local poison center and pediatrician or veterinarian immediately. Save evidence of the plant, even if only the partially ingested bits, to help identify the poison source for appropriate treatment.