Miracle-Gro Has No Place in an Organic Garden

I'm fully aware I'm going to upset some people with this post, but hear me out. If you want to grow an organic garden, you should never use synthetic fertilizers. These are simply products that contain nutrients made in a lab instead of found in nature. In this post, I'll focus on Miracle-Gro since it's a household name that's been popular with gardeners for decades.

There are 10 very good reasons you should avoid using Miracle-Gro and other synthetic fertilizers in your own garden. I'm going to outline each of those reasons, and then — don't worry — I'll give you organic alternatives you can use instead to nurture a beautiful and productive vegetable garden.

10 Reasons Not to Use Miracle-Gro

• Miracle-Gro has a negative impact on your garden soil.
• Miracle-Gro destroys beneficial soil life.
• Miracle-Gro is polluting our water systems.
• Miracle-Gro actually stresses your plants out and makes them more susceptible to pests and disease.
• Miracle-Gro contributes to air pollution.
• Miracle-Gro can actually make your plants less productive and less healthy.
• Miracle-Gro is harmful to human health.
• Miracle-Gro requires fossil fuels in its production.
• Miracle-Grow is made by a company that misleads consumers about harmful substances in their products.
• Miracle-Gro has to be continuously applied.

Miracle-Gro Has a Negative Impact on Your Garden Soil

Those little blue granules contain a concentrated solution of chemicals. According to Miracle-Gro, their water-soluble plant fertilizer contains high concentrations of nitrogen, phosphorus, and potassium (the NPK ratio is 20-20-20), plus some other ingredients like ammonium.

Now, nitrogen, phosphorus, and potassium are all nutrients your plants need, but not at such high doses. Your plants will get a quick boost of nutrients, but what'll happen is your soil health and fertility will actually decrease. That's right.

Using synthetic fertilizers disrupts your soil pH and leads to a buildup of salts and chemicals your plants can't use. You may get big, luscious plants after a couple Miracle-Gro applications, but you'll also deplete the thing that's most important in an organic garden: the great, nutrient-rich soil. The very last thing you want to do is introduce something that will decrease your soil's ability to nurture healthy plants in the future.

Miracle-Gro Destroys Beneficial Soil Life

Okay, this reason is really similar to the last, but I wanted to specifically focus on the microorganisms and worms that live in your soil. You might think of soil as an inanimate object, but it's actually filled with life — there's an entire ecosystem living inside your garden beds. Soil organisms are responsible for breaking down organic matter, cycling through nutrients to make them more available to plants, and improving soil structure. They're absolutely essential for a healthy garden.

Unfortunately, harsh chemicals like ammonium and nitrates from synthetic fertilizers can destroy these microbes in a single season. Beneficial microbes that took years to colonize your soil can be wiped out with a couple doses of Miracle-Gro.

Miracle-Gro Is Polluting Our Water Systems

The next reason you don't want to use Miracle-Gro is because of the chemical runoff. It's easy to assume that the things we put in our garden stay in our garden, but that couldn't be further from the truth. Every time it rains or you water your plants, whatever chemicals you've applied run off and make their way into gutters and — eventually —our waterways.

That means Miracle-Gro flows through our groundwater, our rivers, our lakes, our oceans, and our drinking water. Wildlife is swimming in and drinking Miracle-Gro. Synthetic fertilizers have, in fact, caused something called eutrophication, or "greening" of our waterways. Basically, there's too much algae and not enough oxygen, which is wiping out our aquatic organisms. "Dead zones", areas with little to no aquatic life, have been spreading around the globe since the 1960s (interestingly enough, Miracle-Gro was invented in 1951).

As of now, there's a dead zone in the Gulf of Mexico that's roughly the size of New Jersey. What caused it? Synthetic fertilizer runoff from Midwestern farms traveling down the Mississippi River and into the Gulf.

Miracle-Gro Actually Stresses Your Plants Out

If you wanted to build significantly more muscle mass, you have two choices. One, you could eat a lot of nutrient-rich food, lift weights at the gym, and ensure you get good sleep every night. You'll slowly see changes in your body. It won't happen overnight, but months or years from now, you'll look like a different person. Or two, you could take steroids. You'll probably see fast results, but you'll also experience many unpleasant side effects.

Miracle-Gro and other synthetic fertilizers are like steroids for your plants. If you want your garden to grow big and beautiful, there's two ways to do it. One is naturally: building the soil, planting great seeds and plants, and tending them. It'll take some time, but you'll achieve a beautiful, productive garden.

Alternatively, you could introduce chemical substances into your garden to try to speed up the process. You will get big, productive plants, but at what cost?

This may surprise you, but plants grown with synthetic fertilizers are actually more prone to pests and disease and, at the same time, less capable of protecting themselves from those dangers. They become reliant on the high doses to help them grow fast, and when they find themselves under attack, they no longer know how to lean on their own natural defenses to take care of themselves.

So believe it or not, the synthetic fertilizer that you're using to pump up your plant growth actually makes them weaker.

Miracle-Gro Contributes to Air Pollution

Synthetic nitrogen and phosphorus have extremely harmful effects on air quality. They contribute to the formation of ground-level ozone (not great), thin the protective ozone layer higher up in the atmosphere (really not great), and produce high greenhouse emissions of nitrous oxide, which is even worse for the environment and human health than carbon dioxide (yikes!). It's known to cause acid rain and respiratory problems like asthma.

These environmental impacts, by the way, are a product of both the manufacturing and usage of synthetic fertilizers. Your plants can only take up a certain amount of synthetic nutrients, and whatever they don't use gets reabsorbed into the atmosphere.

Miracle-Gro Can Actually Make Your Plants Less Productive and Less Healthy

The high levels of nitrogen in synthetic fertilizers is great when you want your plants to grow lots of leaves for you. But if you're growing something like a tomato or cucumber, all that nitrogen can cause the plant to keep producing leaves at the expense of flowers and fruit. So you'll get lots of leaves and fewer of the things you actually want to eat.

This is not the case with organic fertilizers, which release nutrients much slower and promote more balanced growth.

Furthermore, if you apply too much synthetic fertilizer, you can actually give your plants fertilizer burn. Too-high concentrations of nutrients damage the roots and leaves of your plants (you'll see yellow or brown edges on the leaves), stunt their growth, and can even kill them. And you're definitely not getting cherry tomatoes from a dead tomato plant.

As if that's not enough, plants grown in overly fertilized soil have been found to be deficient in key nutrients like iron, zinc, vitamin C, carotene, copper, and protein. And isn't one of the reasons to have a vegetable garden in the first place to grow more nutrient-dense food?

Miracle-Gro Is Harmful to Human Health

You're probably already picking up on just how bad products like Miracle-Gro can be for our health, what with them polluting our air and water supply and all. Again, the chemical compounds found in synthetic fertilizers are released into the air and damage our vascular and respiratory systems. Over time, those chemicals can build up in our bodies and cause reproductive issues.

And what about the factory workers who make Miracle-Gro? Research has directly linked exposure to the ammonia used in fertilizer production with acute respiratory effects in workers.

Another thing: Do you remember those soil microorganisms that are killed off by chemicals in synthetic fertilizers? Increasingly, research is linking soil microbiomes with healthy gut microbiomes. Our intestinal microbial community impacts our overall health and susceptibility to disease. So basically, the more synthetic fertilizers we use in the name of growing our food, the sicker we become.

Miracle-Gro Requires Fossil Fuels in Its Production

Another reason not to use Miracle-Gro in your garden is what it takes to make it. I mean, just look at the packaging. It's a big plastic box with more plastic inside to contain all those unnaturally blue granules that were made using fossil fuels.

That's right. Production of synthetic nitrogen fertilizers actually requires a lot of natural gas. Even worse, urea-based fertilizers like Miracle-Gro are responsible for more than 450 million tons of CO2 released into the atmosphere each year. That's a huge carbon footprint!

Every single part of this product costs the environment a lot, and for what? 

Miracle-Gro Is Made by a Company That Misleads Consumers About Harmful Substances

Beyond Pesticides filed a lawsuit against the Scotts Miracle-Grow company in October of 2024 for allegedly misleading consumers about hazardous substances found in their fertilizer products. They claim these products actually contain sewage sludge (or biosolids) contaminated with PFAS, and yet are marketed as "eco-friendly" and "sustainable".

You've probably been hearing about PFAS, AKA "forever chemicals," a lot lately. There are numerous scientific studies showing their detrimental effects on public health and reproduction, wildlife, and pollinators. “Companies that market hazardous substances while claiming environmental and health benefits are misleading consumers who seek out products to protect themselves, their families, and the ecosystems in which they live,” says Jay Feldman, executive director of Beyond Pesticides.

That's not the first lawsuit filed against Scotts. Back in 2012, they were forced to pay a $6 million-settlement for selling pesticides in violation of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).

This is a company that's willing to sell banned pesticides, mislabel harmful products as safe, and ignore overwhelming research about the negative health outcomes of using their products. I don't know about you, but I certainly don't want to support them.

Miracle-Gro Has to Be Continuously Applied

When you use synthetic fertilizers, you disrupt the natural cycle that exists in your garden, and you replace it with a dependent one. Listen, this one dose of Miracle-Gro in your garden isn't going to be just one dose. Because when you introduce synthetic chemicals, you make your plants dependent on them. They'll need to be fed more and more doses of Miracle-Gro to keep them alive.

There's a reason why Scotts Miracle-Gro is a billion-dollar company. 

Is Miracle-Gro Organic?

To be considered an organic fertilizer, the contents have to be derived from living or once-living material (think animal manures, compost, etc.). Organic means naturally found. Thus, it should be really easy to trace the fertilizer back to its source (fish, bones, leaves, food scraps).

Miracle-Gro, as you've probably guessed, is not an organic fertilizer. It is manufactured with man-made ingredients that require heavy use of fossil fuels to produce.

You should, therefore, think twice before using Miracle-Gro in your garden if you care at all about the organic nature of your produce.

Now that we've established why you shouldn't use Miracle-Gro, let's look at what you can use instead.

Organic Fertilizers to Use Instead of Miracle-Gro

Nature has already provided us with soil amendments to help our plants grow. These fall into just two categories: waste from an animal (manure or castings) or decomposed plant parts (compost).

Here are my favorite amendments to add to my organic garden. (Spoiler alert: None of them are bright blue!)

Compost

Compost is the simplest way to increase the health and fertility of your soil organically. My favorite type of compost is mushroom compost. It's inexpensive and easy to find at local nurseries.

Earthworm Castings

This is simply the poop from earthworms. It's very easy to find; you can even make your own with a little worm composting bin.

Leaf Mold

This is another type of compost made from broken down leaves, and it's one of the richest things you can add to your garden. You can make your own with leaves from your backyard.

There are other great options like fish emulsion and kelp meal. These organic options support healthy plant growth by releasing nutrients slowly and improving soil structure. They also feed and support the beneficial organisms living in the soil— all without the drawbacks of synthetic options.

My gardening philosophy is to think about nature. How does nature feed plants in the wild? Then I just try to replicate that in my garden. Nothing else needs to be added.

One more thing: planting your garden intensively (using the Gardenary Planting Method) decreases exposed soil and helps the soil retain nutrients, which cuts down on the number of amendments you need to apply. The way you plant your garden can really make a difference.

Ditch the Synthetic Fertilizers

Always remember that it's not just the plants you're growing that's at stake. The soil is at stake; your health is at stake; the entire planet is at stake.

So next time you're shopping at the garden center, skip the synthetic fertilizers.

Listen, I'm not writing any of this to make you feel bad about using non-organic products in your garden. I didn't start off gardening organically. My grandfather, who was the head of horticulture at a major university, swore by using Miracle-Gro. It took me a while to figure out how I could grow more naturally. It's my simple hope now that more of us will turn to organic, sustainable practices.

I would love it if you'd share this post with your gardening friends who still use the blue stuff on their plants. Help them see how they can grow a beautiful, productive garden without ever having to buy synthetic chemicals.

Sources

• Beyond Pesticides, Lawsuit Targets Scotts Miracle-Gro for Claiming PFAS-Tainted Products Are “Eco-Friendly” and “Sustainable”
• Chemical and Engineering News, "Industrial ammonia production emits more CO2 than any other chemical-making reaction"
• Environmental Protection Agency, "Basic Information about NO2"
• Environmental Protection Agency, "Scotts Miracle-Gro Company Settlement"
• Environmental Protection Agency, "Understanding the Impacts of Synthetic Nitrogen on Air and Water Quality Using Integrated Models"
• International Institute for Sustainable Development, "Why we must rethink the use of nitrogen fertilizers"
• Knowledge Project, "Biological Nitrogen Fixation"
• Miracle-Gro
• National Library of Medicine: "Does Soil Contribute to the Human Gut Microbiome?"
• National Library of Medicine, "Exposure to ammonia and acute respiratory effects in a urea fertilizer factory"
• National Oceanic and Atmospheric Administration: Gulf of Mexico Dead Zone Is Largest Ever Measured
• Nature, "Greenhouse gas emissions from global production and use of nitrogen synthetic fertilizers in agriculture"
• Research Gate, "Synthetic Fertilizers; Role and Hazards"

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