Common Toxic Plants used in Pacific NW Landscaping

You may be surprised how many of the landscape plants surrounding you in your yard are poisonous. Since they can’t run away from predators like animals do, plants rely on toxins, as well as thorns, spines and prickles, as a form of self-preservation. This is the trade-off of having them in our landscapes. They repel the things that can kill them so they can keep our yards beautiful.

Pets are most at risk of poisonous plants. Lists of potential problem plants for dogs and cats have been compiled by the American Society for the Prevention of Cruelty to Animals: https://www.aspca.org/pet-care/animal-poison-control/toxic-and-non-toxic-plants

Here is a non-comprehensive list of common plants used in PNW landscapes. How many are in your yard? Photos of each plant are at the bottom of this article.

Daphne odora emits a wonderful fragrance that drenches the air when it blooms in late winter. All parts can be extremely dangerous, though. The berries are corrosive and will burn your mouth and digestive tract, and even the sap can irritate your skin. Just a few berries can be fatal to a child.

Euphorbia produces milky sap when cut. This sap is a skin irritant for humans but is more toxic to animals if ingested.

Hostas are toxic to most animals. However, deer love them.

Hellebores will cause severe vomiting if eaten.

Larkspurs (Delphinium species): Seeds and young plants are most toxic.

Foxglove (Digitalis purpurea) contains several toxins that are active in the fresh, dried, or even boiled plant.

Cherry-tree twigs and foliage contain a compound that releases cyanide when chewed.

Spring flowering bulbs: These toxic bulbs include Daffodil, Hyacinth, Autumn Crocus, Snowdrop and Star-of-Bethlehem.

All parts of the following popular ornamental plants are toxic:

Black locust
Japanese Yew
Oleander
Wisteria
Morning glory

Pokeweed is one of the most common sources of plant poisoning in the United States. It’s an invasive plant but most residents don’t remove it because it has bright pink stems and shiny berries which look similar to blueberries. However, all parts are extremely toxic.

Nandina berries have a type of cyanide that is extremely toxic to all animals, including birds.

Skimmia can cause cardiac arrest if large quantities of its berries are ingested.

What About Native plants?

Our Northwest native plants aren’t immune from this list, either. These natives grow easily in yards as well as the wild, but certain parts can be toxic if ingested:

Mahonia (Oregon Grape): Consume in moderation, as the berries can be toxic in excess.

Rhododendron leaves and flowers will cause mild symptoms if ingested.

Elderberry: All plant parts should be considered toxic, especially the roots. However, the berries are harmless once cooked.

Milkweed: The leaves, pods, seeds and sap of various species are toxic.

Lupines: Some species are toxic and others are not. The toxic agent is primarily contained in the seeds.

Red and White Baneberry: All parts are poisonous, but its berries are most toxic.

Should You Care if a Plant is Toxic?

After all this fear-mongering, the bottom line is you should have nothing to worry about as long as you use common sense. The worst symptoms that these plants exhibit happen mostly if they’re ingested. This shouldn’t be of much concern unless you have a child or pet that is prone to eating things unsupervised. Even if ingested, there’s a good chance they’ll vomit before it causes serious damage. Plus, if you’re not watching what your toddlers are eating outside, you probably have more to worry about than the plants in your yard. Most dogs don’t eat everything they see. However, it’s always good to have the knowledge of what’s toxic in case someone brings a dog over that does.

So continue enjoying your beautiful yard, now that you know which plants not to eat!