The Reasons Why Synthetic Chemical Fertilizers like Miracle-Gro Are So Bad for Your Garden

Is Miracle Gro Bad? Is miracle gro toxic? Does miracle grow work?

Updated March 21, 2024

You most likely found this article on a Google Search — it is, to my surprise, the #1 search result on the entire internet for “is miracle gro bad” (the folks at Scotts must love me!) A lot of people have become seemingly enraged after reading this post, based on the nasty comments they left (it is to my amusement that people get so upset over fertilizer)… while other people have left this page inspired to garden in a different way.

I am a regenerative flower farmer in Western New York, just north of Buffalo. I have experience growing organic farms and gardens professionally for 12 years. I started as an urban farmer, growing nine urban food plots in Detroit, then I became an edible landscaper in Chicago where I gardened for families in over 150 backyards. Now I own my own flower farming business where I operate my own flower farm in an earth-loving, regenerative way.

All of the resources I’ve used to gain the information on this blog, and in this post, are at the bottom of this blog entry. I encourage you to check some of these books out. If you’re a gardener, they will change your life in the best way.

I don’t intend to shame you for using Miracle-Gro. I started this garden blog to help people become better gardeners by working with, not against, earth’s natural systems. But I will straight up say, that NO Miracle-Gro products belong in our gardens, especially that blue crystal stuff you may have added to a watering can in the past.

Richter’s Herbs is our favorite herb plant supplier!

The blue color of those crystals is derived from copper sulfate. I’ve grown over 150 vegetable & flower gardens and I have never seen nor heard the need of using copper sulfate in the garden, except as a fungicide. If you do not have fungal blight (a serious plant disease) you should not be using copper sulfate in your garden (and I would argue there are better solutions than a fungicide to deal with your fungal blight problem). Fungicide will effectively kill all of the positive fungal connections in the soil. Copper sulfate is also a bactericide, and as such, is incredibly harmful to soil life.

Read this post when you’re done with this one: How to ‘Fix’ Your Garden Soil After Using Chemical Fertilizers

Anything with the Miracle-Gro label should be avoided entirely: Bagged potting soil and garden soil, ‘Shake n Feed,’ the blue crystals, and yes, even so-called “Organic” Miracle-Gro products should be entirely avoided.

Here’s why:

Miracle-Gro makes gardening effortless for everyone. Even those with the most challenging gardens that use MG will have a wildly successful garden season. Miracle-Gro helps plants grow huge by outsourcing the jobs of naturally-occurring soil microbes and leaving plant nutrition up to water soluble synthetic fertilizers. These water soluble fertilizers are heavy in salt and are harmful to soil microbes — the living, breathing organisms that have an actual job of providing nutrients to our plants.

Miracle-Gro supplies an enormous amount of plant-ready available nitrogen so that plants can grow big, bushy, green, and FAST. The problem with MG is that the nitrogen is derived from synthetic ammonium and water soluble nitrates, producing off-chemicals that are harmful to soil microbes, worms, and all other forms of life in the soil. MG is so strong that if used incorrectly, the fertilizer will actually burn the leaves and roots of your plants (you may have already experienced this). Imagine what it’s doing to the healthy bacteria, fungi and other soil microbes that are working so hard to provide the nutrients your plants need.

There’s more… soil life isn’t the only thing synthetic fertilizers destroy.

We all know our waters are polluted (all of them: ponds, lakes, rivers, oceans) — but did you know that synthetic agricultural fertilizers are one of the main culprits of our polluted streams, rivers, lakes and oceans?

In heavy rains, agricultural fertilizers run off into streams, lakes and eventually make it to oceans. High nitrogen fertilizers are critically harmful to fish and other marine life, causing algae to grow in excess; large expanses of algae are known as “algae blooms.” Algae blooms grow so thick toward the ocean’s surface that they block sunlight required by other marine life to survive. For example, The Gulf of Mexico has thousands of kilometers of “dead zone” caused by algae blooms, all caused by fertilizers used on conventional farms running off into streams that feed the Mississippi River.

You might be thinking, What do algae blooms and river pollution and all that got to do with my small veggie garden?

Well, these “bigger” environmental issues have everything to do with you, as a gardener and consumer. Your garden matters because of the dollars you spend.

You can either choose to spend your money on companies that create products that are profiting by destroying our planet (such as Scotts, who make Miracle-Gro), OR you could buy from companies that create gardening products that nurture environment and the creatures/humans living in it, because they give a damn. A few of these good companies include: Neptunes Harvest, Plant Success Organics, and Down to Earth. Some of these companies’ products are readily accessible at Home Depot and Lowe’s stores! ALL of it is accessible online.

The difference between synthetic fertilizers (like Miracle-Gro) and organic fertilizers (such as those made by the brands listed above), is that synthetics are made in a lab and organics are made from real plant and animal materials. I like to compare our gardens to our guts. Our guts are full of microbes, the good ones of which we need to nurture so the rest of our bodily systems function at their best. We can’t nurture our bodies and stay healthy on a diet that consists entirely of Cheetos, McDonald’s cheeseburgers and Snickers bars. To stay healthy and functioning, we know we should nourish our bodies mostly with fresh vegetables, fruits, whole grains, nuts & seeds, and lean, grass-fed meats (if you’re a meat eater).

Our garden microbes aren’t any different than our gut microbes. Soil microbes can’t survive entirely on lab-made fertilizers just like we can’t survive entirely on lab-made food.

OUR FAVORITE ORGANIC FERTILIZERS for gardening ARE:

homemade or good locally-sourced Compost + Compost Tea
Kelp Meal
Mycorrhizal Fungi Inoculant (technically not a fertilizer, but it’s the #1 important ingredient I use during planting to inoculate the soil with beneficial fungi)
Alfalfa Meal
Leaf Mulch/Shredded Leaves (not a fertilizer, but if you learn how to use leaf mulch it will add incredible organic matter, earthworms, and microbes to your garden, and these creatures will naturally break down the leaves into usable plant nutrients over time)
These items above, for the most part, are all you’ll ever need to use in your garden.
Learn more about applying & using organic fertilizers here (this post is written for flower farming, but flowers & vegetables have many of the same needs, so this information can be applied to your home veggie garden).

Myco Bliss - Mycorrhizal Inoculant for Plants - 5 Superior Strains - Organic Mycorrhizae Root Enhancer - Increases Nutrient Absorption & Crop Yields (1lb, Powder)

Plantonix

Buy on Amazon

Kelp Bliss - Pure Kelp Meal - Organic Kelp Fertilizer for Growing Healthy Plants, Crops, and Gardens! Increases Fruit and Vegetable Yield! (5 lbs)

Plantonix

Buy on Amazon

Down To Earth Alfalfa Meal Natural Fertilizer 2.5-.05-2.5 OMRI

DOWN TO EARTH DISTRIBUTORS INC

Buy on Amazon

So, the biggest question is… Do you give a damn?

If you do, then I encourage you to spend your money like you do. Feed your plants like you give a damn. Feed yourself and your family like you give a damn. You’re obviously reading this because you give a damn, right?

The greatest thing we can do is educate ourselves and share knowledge with others in a respectful way. I’ve written many other blog posts to help you garden healthfully - see some of the links below.

A NOTE ABOUT SOURCES IN THIS ARTICLE

The information in this article (namely the claim that synthetic fertilizers are harmful to soil microbes, and therefore, our health) has been derived from a handful of books I've read on the topic of Regenerative Agriculture. All of the information in these books has been researched and written by professional agronomists, biologists, entymologists, among others with differing science backgrounds, and farmers in actual practice. These people include John Kempf, Gary Zimmer, Kris Nichols, Jonathan Lundgren, Tom Dykstra and Gabe Brown. As such, I feel comfortable sharing this information with the world on my blog.

I highly recommend the following resources, which have completely changed the way I garden based on my knowledge of soil microbiology and the relationship of their health, soil health, and our health:

Best Book To Start With: "Teaming with Microbes: The Organic Gardener’s Guide to the Soil Food Web" by Jeff Lowenfels

Book: "Quality Agriculture: Conversations about Regenerative Agronomy with Innovative Scientists and Growers, Volume One" by John Kempf (includes specific chapters regarding the negative impact of synthetic fertilizers)

Book: "Teaming with Nutrients: The Organic Gardener’s Guide for Optimizing Plant Nutrition" by Jeff Lowenfels (includes specific information regarding the negative impact of synthetic fertilizers)
Book: "Dirt to Soil: One Family's Journey into Regenerative Agriculture" by Gabe Brown (the whole book describes the farmer’s process of coming to terms with synthetics)
Podcast: No-Till Market Garden Podcast
Podcast: Growing For Market Podcast

Podcast: Regenerative Agriculture Podcast