There’s no denying the beauty of a lush, green lawn. Keeping it that way can require lawn treatments that promote grass growth while keeping bugs and weeds at bay. However, some of these products—even the natural ones—can harm pets.
Pesticides and Pets: Products to Avoid
Pesticides are designed to kill pests. But some can be toxic to pets, as well.
For example, the granule form of bifenthrin, a popular insecticide, can cause symptoms like vomiting, diarrhea, body tremors and even seizures, says Dr. Charlotte Flint, a board-certified toxicologist and veterinarian at Pet Poison Helpline. “Bifenthrin sprays are safer and do not cause as many problems as granules, especially if applied appropriately and if a dog does not have access to the wet spray,” she says.
Flint also recommends avoiding organophosphate insecticides, which can cause drooling, vomiting, diarrhea, difficulty breathing, tremors and seizures if a toxic amount is ingested. “Fortunately, many of the more toxic versions are no longer sold or are more tightly regulated,” she says.
Another pesticide to avoid is metaldehyde, which is found in some slug and snail bait granules and can cause tremors, seizures, high body temperature and liver failure.
Herbicide and Fertilizer Safety
Most herbicides are diluted with water to a very low concentration, making them less dangerous than most pesticides.
“Once they have been properly diluted, applied and dried, we see few issues,” says Flint. “I think it is OK to use most herbicide lawn treatments as long as they are applied properly and people keep their pets off the lawn until it has fully dried.”
Generally, most lawn fertilizers cause only stomach upset when ingested, says Flint. “Common ingredients in fertilizers such as nitrogen, phosphorus and potassium are poorly absorbed by a dog’s stomach, so systemic effects are rare,” she adds.
However, fertilizers with high amounts of iron may carry a risk of poisoning. “If enough is consumed, iron poisoning can cause more severe vomiting and diarrhea, which might contain blood, and possibly liver damage,” cautions Flint.
Organic and Natural Lawn Treatments: What You Need to Know
Organic fertilizers usually contain ingredients like bone meal, blood meal, feather meal and manure—all of which dogs find appetizing. Ingesting these ingredients can cause vomiting and diarrhea.
“Large amounts of fertilizers like bone meal and blood meal can sometimes cause more serious effects like pancreatitis or an obstruction in the stomach or intestines,” says Flint.
Milorganite, an organic ingredient in some fertilizers, can cause more severe stomach upset, muscle weakness and pain, adds Flint.
Another natural product to avoid is cocoa mulch, which is made from the shells of cocoa beans. Many dogs enjoy the taste, but like chocolate, it can be toxic. “Depending on the amount, ingestion of cocoa mulch can cause a range of clinical signs from vomiting and diarrhea to muscle tremors, elevated heart rate, hyperactivity and even seizures,” says Dr. Tina Wismer, medical director at the ASPCA Animal Poison Control Center in New York City.
Wismer recommends less toxic alternatives—such as shredded pine, cedar or hemlock bark—but warns that ingesting mulch is never a good idea. “Any type of mulch can cause stomach upset or even an obstruction in the stomach or intestines which can require surgery to correct,” she says. “Keep pets from eating any type of mulch.”
How to Protect Your Pet
Before buying any pesticides, herbicides or lawn treatments, carefully research the products. If using a landscaper, be sure to mention you have pets and come up with a plan.
“I recommend having a conversation with your lawn company if you have pets, and find a company knowledgeable about pet safety,” says Flint. “Many companies will help you pick safer products, can provide information about possible risks to pets, and can help advise on how to keep pets safe, especially around the time of application.”
Keep all lawn care products out of your pet’s reach. “Most poisonings from lawn treatments like fertilizers and herbicides occur when pets get into a package and consume a lot of it,” says Flint. “Dogs will readily eat pounds of these fertilizers if they have access to a bag and the opportunity.”
When using products, always follow the instructions. “Make sure you apply any herbicides or pesticides per the manufacturer’s directions, including appropriate dilution, and keep pets out of treated areas as long as the manufacturer recommends,” says Wismer.
When in doubt, reach out to your veterinarian for advice about safe lawn care products.