House and Garden Plants Potentially Poisonous to Pets

By Ann M. Mason, Fairfax Master Gardener Intern

Easter Lily

Easter Lily

As a dog lover, I am struck with my dog’s concentrated determination and focus for eating grass after bounding joyously out of the house for a walk or for a potty break. Having ingested grass, my dog returns to the house and immediately throws up on the same carpeted place just inside our front door. This raises the question, “Is grass toxic to my dog?” I am not alone in asking this question. While staffing our Master Gardener table at plant clinics. we’ve been asked the question, “What garden plants are toxic to pets?”

Now that the weather is cooler, gardeners are putting their gardens to bed, planning for spring plantings and adding seasonal plants and flowers to their homes. So, beyond the question of toxic plants in the garden, in this article we explore the broader question, “What indoor and outdoor plants are potentially poisonous to dogs and cats?”

Naked Lady

Naked Lady

Animal scientists at the American Society for the Prevention of Cruelty to Animals (ASPCA) report that “consumption of any plant material may cause vomiting and gastrointestinal upset for dogs and cats.” From toxicology we know that both the amount (the dose) and the severity of the toxicant play an important role in the severity of any poisoning event. Plants are not equally toxic; nor do all plant parts pose the same level of concern. To differentiate the differences in toxicity, experts established a numeric 4-scale system: They assigned a score of 1 to a plant with major toxicity — the potential to cause serious illness or death if ingested; 2 for plants with minor toxicity where ingestion may cause vomiting or diarrhea when ingested; 3 for plants where the juice or sap contain needle-shaped oxalate crystals that can irritate skin, mouth, tongue and throat that can result in throat swelling, breathing difficulties, burning pain and stomach upset; and 4 for plants where contact can cause skin rash, irritation. Some plants have a score of 1 or 2 and 4, meaning that they could pose both and ingestion and skin sensitization hazard.

After my research I was relieved that the experts do not list grasses