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Is Dog Poop Good Fertilizer? (6 Reasons the Answer Is No)

A healthy puppy produces a lot of poop, but how does it affect grass?

A healthy puppy produces a lot of poop, but how does it affect grass?

Is Dog Poop Good for Grass?

There is a misconception out there on the Internet about dog poop being good for grass and acting as a fertilizer. This misinformation likely stems from people conflating dog poop with cow manure, which is widely used as a crop fertilizer. Though they are both excrements, cow manure and dog poop are very different in terms of their chemical makeup. In other words, not all poop was created equal.

This article will break down the six primary reasons why dog poop is not a good fertilizer and is actually bad for the grass growing in your neighborhood lawns. It can also be dangerous to the health of your family and community, which is why it’s important to scoop it up.

Unlike cow manure, your dog's poop does not act as a fertilizer.

Unlike cow manure, your dog's poop does not act as a fertilizer.

6 Reasons Not to Use Dog Poop as Fertilizer

A dog with a healthy gut absorbs the nutrients from his high-protein diet. What gets left behind is the smelly poop, which is acidic, slow to decompose, and full of bacteria and parasites. As you can probably guess, this does not make for a good fertilizer. But let’s look at the chemical breakdown to see why.

1. It’s Full of Bacteria

Dogs have a lot of bacteria in their guts, but their digestive systems are usually healthy enough to eliminate it. It’s been estimated that one gram of dog poop can hold 23 million bacteria. That bacteria is not conducive to plant growth obviously, so you don’t want it in your soil or near a garden where you may be growing vegetables.

2. It May Contain Harmful Parasites and Diseases

In addition to bacteria, dog poop can contain parasites and diseases, including:

  • Parvo virus
  • Hookworms
  • Giardia
  • Roundworms
  • Trichinosis
  • Campylobacteriosis
  • Cryptosporidiosis
  • Echinococcosis
  • Salmonella

Like bacteria, parasites and diseases can easily spread to humans. All it takes is someone sitting in the grass for a moment and unknowingly contaminating a hand or tracking some particles inside.

3. It’s Too Acidic and Nitrogen-Rich

One of the biggest misconceptions about cow manure vs. dog poop has to do with the microbiomes of these animals as well as their diets and the chemicals involved in digestion. First, let’s consider the diet of a cow, which is primarily plant-based: grass, grain, hay, soy meal, cottonseed, corn silage, etc. The resulting waste is low in nitrogen and full of undigested, nutrient-rich plant fibers, which is why it makes for an effective crop fertilizer.

Dogs, on the other hand, eat a protein-rich diet, which makes their poop very acidic and full of nitrogen. While grass does need some nitrogen, dog poop has way too much; after the poop has decomposed for a while, the grass will die from the excess nitrogen and have to be reseeded. Interestingly, the nitrogen is released into the soil slowly, which can initially make it look like the grass is growing tall and dark green (probably another source of the fertilizer misinformation). Eventually though, after as long as a year of decomposing, this same grass will turn yellow and then brown as it dies.

4. It Takes a Very Long Time to Break Down

As suggested above, dog poop takes its time to decompose. How much time? The answer is variable, depending on environmental conditions and the dog’s diet. On average, dog poop takes about nine weeks to break down and decompose. But in colder climates, it can take up to a year. After the first two or three weeks, any bacteria present will pose a risk; by week four, any parasitic eggs or larvae present start hatching; and by week six or seven, mold starts spreading.

5. It’s Super Stinky

No poop smells good—to humans, at least—but dog poop is particularly smelly. This has mostly to do with the high-nitrogen, acidic waste we discussed earlier. But the smell of dog poop can also be affected by certain kibble products that contain large amounts of fiber and other nutrients, like grains and starches, that dogs’ bodies weren’t meant to absorb and which excrete particularly smelly gasses when digested.

In any case, manure, which is great for fertilizing, is bad enough—dog poop is not something you want to fill the air around your garden or yard.

6. You Could Be Fined

Most states and cities have laws—the so-called “pooper scooper laws”—imposing hefty fines on dog owners who do not clean up their dog's poop. This is because pet waste pollution is actually a legitimate public health concern. Rain transmits dog and other animal feces into local water sources, and the resulting algae blooms and weeds can be toxic.

There are "pooper scooper" laws in provinces and countries around the world.

There are "pooper scooper" laws in provinces and countries around the world.

Can You Compost Dog Poop?

While there is broad consensus about dog poop making for terrible lawn fertilizer, some debate has taken place over whether it can be composted. Dr. Mark, a veterinarian with over four decades of experience working with dogs, traces the confusion back to Steve Solomon's influential book Organic Gardeners Composting, which advised not to compost dog poop.

But Dr. Mark says dog poop can be composted—if the right precautions are taken. According to research conducted at the University of Minnesota and the University of Oregon, when heated to temperatures of 130-165 degrees, any pathogens in the dog poop will be destroyed. While composting takes some effort, Dr. Mark describes several benefits:

  • It provides organic nutrients for your trees or lawn (once it has composted correctly)
  • You don't contribute to the tons of refuse being piled into already overloaded landfills and sewer systems
  • You don't contribute more plastic waste from daily bag use

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.