Is Portulaca Toxic to Dogs? What the ASPCA Says About Moss Rose

Portulaca is the low, jewel-toned succulent you see spilling out of hot, sunny beds and container edges all summer. It is easy to grow and easy to love, and it also earns a real toxicity warning. This page covers what the toxin does, how worried to be, the difference between the weedy and ornamental forms, and what to plant instead if you want the same low sunny color without the risk.

What the ASPCA says

The ASPCA Animal Poison Control Center lists Portulaca (Portulaca oleracea, also sold or found as moss rose, purslane, wild portulaca, rock moss, pigweed, and pusley) as toxic to dogs, cats, and horses. The toxic agent is soluble calcium oxalates. The ASPCA files this plant under two names, Moss Rose and Portulaca, and both point to the same species and the same soluble-oxalate chemistry. In dogs, casual ingestion most commonly causes drooling and stomach upset rather than a life-threatening event, but the ASPCA lists it without qualification, so it belongs on the caution list.

Soluble calcium oxalates are the same class of compound that makes many common houseplants irritating to chew. The plant is worst for grazing livestock that eat large amounts, per the Merck Veterinary Manual, which describes soluble-oxalate plants causing acute low blood calcium and kidney crystal formation in animals that graze them heavily. For a dog or cat that nibbles a stem, the realistic picture is oral and stomach irritation with drooling, not renal failure.

How much portulaca is dangerous for a dog?

The ASPCA lists portulaca as toxic without naming a safe dose, so there is no amount you can treat as harmless. In practice the risk scales with how much was eaten. A dog that mouthed a single stem is a different situation from one that ate a large mouthful of foliage, but both are worth a call. The soluble-oxalate irritation tends to show up as drooling and stomach upset rather than a delayed crisis, so the amount and what you saw the dog do matter more than waiting. Call the ASPCA Animal Poison Control Center at (888) 426-4435 with your best estimate of how much was eaten rather than guessing whether it was enough to matter.

What are the signs of portulaca poisoning in dogs?

The ASPCA lists the signs across its two entries for this plant. The Moss Rose page names kidney failure (rare in dogs and cats), tremors, and salivation. The Portulaca page names muscle weakness, depression, and diarrhea. Put together, the common real-world signs in a dog are drooling, an upset stomach with diarrhea, and lethargy or weakness, with tremors and kidney effects at the rare and severe end. The Merck Veterinary Manual notes that the serious soluble-oxalate outcomes, low blood calcium and kidney crystals, are seen mostly in livestock eating large amounts, which is why kidney failure is flagged as rare for dogs and cats. Report any of these signs when you call poison control.

Is portulaca toxic to cats too?

Yes. The same ASPCA Animal Poison Control Center listing covers cats and horses alongside dogs, and the soluble calcium oxalates are the same across species. Cats that chew garden foliage or houseplants can get the same oral and stomach irritation, so keep portulaca out of reach the way you would for a dog. If you have a cat that grazes plants, this is one to place where the cat cannot reach it, or to skip.

Weedy purslane versus ornamental moss rose

Two plants share this genus and this warning. The weedy purslane in sidewalk cracks and vegetable beds is Portulaca oleracea, which is exactly the species the ASPCA lists. The showy bedding plant with the bright pink, orange, and yellow flowers sold as moss rose is Portulaca grandiflora. The ASPCA does not list grandiflora separately, but it is the same genus with the same soluble-oxalate chemistry, so the honest answer is to treat it the same. If your dog actively eats plants, do not rely on the ornamental form being safer.

We cover the edible weed in more detail in our post on whether purslane is toxic to dogs. That page is about the weedy Portulaca oleracea people forage and eat. This page is about the ornamental moss rose you buy in flats, but because they are the same genus, the caution carries across both.

Dog-safe native swaps with the same look

These Edwards Plateau natives (San Antonio area) give you the same low, sun-loving, drought-tough color without the ASPCA listing. Native ranges per the Lady Bird Johnson Wildflower Center.

What to do if your dog ate portulaca

• Note which part was eaten (stems, leaves, flowers) and roughly how much.
• Call the ASPCA Animal Poison Control Center at (888) 426-4435, or your vet. The soluble-oxalate irritation can start soon after eating.
• Do not induce vomiting unless a vet tells you to.
• Watch for drooling, diarrhea, weakness, lethargy, or tremors and report them on the call.

For the rest of the plants worth checking before your next nursery run, see the six Texas yard plants most toxic to dogs and the dog-friendly native backyard guide.