Best Organic Lawn Fertilizer

What is the Best Organic Lawn Fertilizer?

Grass has been growing on earth for millions of years, and it did fine before the use of chemical fertilizers keeping weeds away. That’s why people are making a change towards organic lawn care. Not only is it safer for children and pets, but it has less of an impact on the environment in our community, and is healthier for the wildlife that shares our yards. In this article I’ll share what I consider to be the best organic lawn fertilizer

The shift to organic lawn care isn’t for everyone. Going organic requires an additional time investment and it requires a lot of patience, but for me (and others) the effort is worth it for the safety.

Trust and Accuracy Information

This article was last updated on by Lawn Chick Owner Sarah Jameson
Article content reviewed for accuracy by Horticulturist Arthur Davidson, A.S.

If you’ve been using chemical treatments on your grass for years, the biggest challenge of going organic is getting your yard used to using its natural defensive abilities again.

Why Use an Organic Lawn Fertilizer?

Synthetic fertilizers and pesticides step in and fulfill roles grasses evolved to do on their own. If your lawn isn’t used to tending to itself, you’ll need to be patient as it grows in again. Unfortunately, that means you’ll need to tend to it more strictly for 1 to 2 years.

The payoff? Once it’s grown in again, you’ll find it’s greener and lusher than ever before! is reader supported. If you make a purchase after clicking a link, I may earn a commission at no additional cost to you.

Getting Your Lawn Ready to Go Organic

After making the decision to make your lawn chemical-free, the first thing you need to do is stop applying all chemicals. Cut it off completely.

Then do a soil test (I’ve used this kit from Amazon with good results). The key to a healthier, organic lawn is to make your soil rich in nutrients so the grass can fend for itself. It’s more sustainable in the long-term, and it means less work for you overall.

A soil test will tell you which nutrients your lawn is lacking, and that will give you a guideline of what to fix and how to amend the soil.

Do a Soil Test to See What Your Lawn Needs to Thrive

Local nurseries or universities offer soil tests, and they’ll send you sample boxes to fill to ship back. The soil test kit I linked above works the same way. You’ll need to dig up samples from different areas of your lawn and send the soil in to be analyzed in a lab.

When you get the results, you can purchase the products you need to improve your lawn, like buying gypsum if your lawn has calcium deficiencies.

Part of going organic is that you’re working on your soil, not your grass. That thick, green, beautiful carpet of grass will come when you get the soil balanced and fertile, naturally.

Preparing Your Lawn to Amend it with Nutrients

Preparing your lawn to accept the organic fertilizer and nutrients it needs is just as important. Here’s how you should do that:

  • Mow your lawn down to about 2-inches, so the nutrients can get as much soil contact as possible. I recommend bagging your clippings on this mow so there’s as little between your fertilizer and the turf as possible.
  • Pull up any weeds you find and then de-thatch your yard using a thatch rake or power rake.
  • Once those tasks are done, it’s time to aerate your lawn. You can either hire someone or rent an aerator. I like to rent a commercial power rake and aerator and do everything the same day (one in the morning and one in the afternoon). This can save you money by doing 4 hour rentals on each piece of equipment vs. full day rentals on both.
  • Now your lawn is ready to absorb all the nutrients you’ll add to your yard.

The other incredibly beneficial thing you will want to do is add a quarter-inch to a half-inch of organic compost over your yard after spreading the nutrients your soil test told you you’d need.

Compost is decomposed organic matter that carries the beneficial organisms to make your soil rich, and your grass healthy. These are nematodes, fungi, and other bacteria. It improves soil structure, especially in nutrient poor soil, like those that are sandy or full of clay.

It’s easy enough to start a compost bin in your backyard, and often local communities make public compost depositories. Worst-case, order some in bulk from your local nursery. This is black gold and it’s worth every penny.

Art Davidson, a horticulturist with five decades of experience and a member of Lawn Chick’s expert panel, adds that “well seasoned compost is always the best way to build up the soil to feed your lawn.”

A Greener Lawn (In Color, Too)

Organic fertilizers don’t act as quickly as synthetic fertilizers, and you won’t notice your lawn gets green quite as quickly after an application of even the best organic lawn fertilizer.

Synthetic and quick-release fertilizers target the grass specifically and do nothing for the soil, whereas the organic counterpart improves the soil to strengthen the grasses.

Organic Lawn Care

The benefit to that is organic fertilizers act more slowly and require fewer applications. That’s particularly beneficial because it offsets the higher price tag at purchase. A bag of organic fertilizer might be more expensive, but if you’re only applying it 3 times per season, the cost evens out.

Chemical vs Organic Lawn Fertilizers

Chemical fertilizers are full of synthetic nitrogen, phosphorous, and potassium that deliver quick, excessive amounts of each nutrient to your grass.

Organic fertilizers release smaller, more consistent amounts of nutrients to let your grass develop the capabilities to fend for itself by developing deeper root systems, in addition to being thick enough to crowd out weeds.

Over-apply a synthetic fertilizer and you risk “burning” your lawn (think of the difference between eating one buffalo wing vs. drinking a quart of buffalo wing sauce).

Organic Fertilizer for Lawns

Most organic slow-release fertilizers won’t burn your lawn, and your biggest risk that comes with over-applying it is that you will lose out on the money you spent.

The other important factor when getting used to organic fertilizers is the fertilizer’s NPK, or its ratio of Nitrogen, Phosphorous, and Potassium (Potassium is “K,” like on the periodic table).

These key nutrient numbers are lower and more varied in organic fertilizers, while chemical fertilizers have higher numbers and tend to deliver more than is needed.

The lower NPK in organic fertilizers is why it takes longer for your lawn to show its effects. In the long-term, your lawn will be healthier, as it’s more sustaining and sustainable.

Most organic lawn fertilizers have a higher nitrogen rating, and generally more potassium than phosphorous. Usually no organic fertilizer will have NPK numbers higher than 15.

My Picks for the Best Organic Lawn Fertilizer (What I Use)

Fertilizers like Milorganite (what I consider to be the gold standard and best organic lawn fertilizer) have an NPK rating of 5-2-0, and it is primarily heat-dried microbes. It’s one of the most popular brands and spreads easily using a handheld broadcast spreader, drop spreader, or broadcast spreader.

The low NPK ratios of Milorganite means results come slowly, but it improves the strength of the grass overall, and the iron in it will help your grass achieve that dark green color everyone is after.

Purely Organic Lawn Food is another highly reputed brand of organic lawn fertilizer, and it’s one that I use on my own lawn and have had good results with. Its NPK rating is 10-0-2, meaning it will make your lawn a rich green color. The potassium strengthens the grass roots for drought protection. I like to use it as a follow-up fertilizer after applying starter fertilizer to new grass.

There are regulations prohibiting use of phosphorous in a lot of fertilizers, since it can be harmful to the environment, but it helps newly seeded grass take root.

One organic fertilizer that balances its NPK is Dr. Earth 715 Super Natural Lawn Fertilizer. Its NPK of 9-3-5, and this ratio will develop a strong root system and makes your grass strong quickly enough to cut down on water waste.

Green Practices

Choosing the Best Organic Lawn Fertilizer for Your Lawn

There are several other steps you can take to make sure your lawn is green in both its health and environmental consciousness.

Overseeding your lawn every year is a great way to keep weeds out of your lawn because it makes the grass thick enough to stop them from growing.

Choosing an organic grass seed, or one specific to your climate is important for keeping your work down and keeping chemicals out.

Matching your grasses with your climate and soil-conditions is an important step, which will make your lawn require less work than sustaining non-native grasses in adverse conditions.

And the long-term benefit of going organic with your lawn is that your lawn will eventually find a balance and require a lot less work from you to maintain.

Keeping Your Lawn Green with the Best Organic Lawn Fertilizer

After establishing your lawn, the basic principles of lawn care are still important.

Make sure you cut your grass to the appropriate length for your species. Most lawns in America are healthiest at about 3 to 4 inches high, like bluegrass and fescue. However, warmer season grasses, like Bermuda grass, can be cut much shorter.

Using a mower with a mulching attachment is also incredibly helpful, since grass clippings provide natural fertilizers, giving your lawn a healthy dose of nitrogen as it decomposes.

Make sure to spread out any grass clumps evenly. Rake up any wet clippings if you mow your grass when it’s wet. This way you will not suffocate your grass.

Using the Best Organic Lawn Fertilizer to Make Your Lawn Green & Healthy

Until your lawn is established, unfortunately, you may notice more weeds growing in your yard. It will take some time for your lawn to grow in strong enough to force them out. You’re not without organic solutions for weed and pest prevention, however.

In early spring, you can spread corn gluten meal onto your lawn to prevent weeds. It’s an organic weed preventative, but gluten meal does target all plants. If you spread it when overseeding or starting a new lawn from seed, it’ll keep grass from germinating as well.

Other options are natural post-emergent weed killers, such as Nature’s Avenger.

Alternatively, you can home make a weed killer for your lawn using a diluted solution of dish soap and lemon juice. Diluted vinegar can also work.

You can use similar solutions to eliminate ants naturally.

At Lawn Chick, I am committed to publishing accurate, useful, and trustworthy resources for my readers. As part of this commitment, I’ve invited subject matter experts to review our articles for accuracy. I invite you to read our editorial policy and publishing standards which outlines in detail how every article on this site is sourced, edited, fact-checked, and vetted.



Sarah Jameson’s blog, Lawn Chick, is read by over 2 million homeowners each year and she is regularly cited as an expert source of lawn care knowledge by major publications. Her goal is to meet you where you are, and help you achieve a yard you’ll be proud of. Ready to take the next step toward improving your lawn? Grab her free lawn care cheat-sheet: What to Do When - Take the Guesswork Out of Lawn Care, or upgrade your garage by browsing her favorite DIY lawn care products.

10 thoughts on “What is the Best Organic Lawn Fertilizer?

  1. David M Nouman

    I used to use Milorganite, but something in it makes my daughter’s eyes swell up and she is allergic to it. I’ve switched to using soybean meal and alfalfa pellets from my local feed store. Results are fantastic and price is right. Alfalfa also helps new seedlings develop…and our neighborhood bunny loves our yard!

    • Sorry to hear that about your daughter, David! It’s the first time I’ve heard of anything like that, so thanks for sharing your experience.

      I think the deer would never leave my lawn if I tried soybean meal and alfalfa pellets, but I’m glad it’s working for you.

  2. Eric

    Hi Sarah. Is there anyway you can share your yearly lawn plan as far as what products to apply and when? I’m looking to stay 100% organic as I’m concerned about synthetic chemicals with 2 small children and a dog. Thanks!

    • Hi, Eric!

      I’m actually working on an in-depth eBook about this right now which I’ll be giving away for free to my readers. I can email you when it’s finished if you like?

      For now I can tell you that for organic lawn care I like to use Espoma’s corn gluten product as an organic pre-emergent to block weed germination in the spring, and I use a combination of Milorganite 4x annually (here’s my article with that application schedule) as a slow-release organic fertilizer. The Purely Organic Lawn Food is a good product which I’ve used in the past as well, though I prefer Milorganite.

      Every-other year I also top-dress in the fall when I do my aeration and overseeding, and I use screened compost for that – a great organic option to improve your lawn naturally. Here is my aeration and overseeding guide, and here is a guide about top-dressing your lawn. Hope all of this is helpful!

      • Mike

        I have used Milorganite for 5 years now. It not only helps the grass but also helps to change the soil and promote microbial activity over a period of time.

      • Donna

        Sarah, I used corn gluten early spring (Chicago area) and have more weeds than ever. I applied early, obviously not early enough. What can I do to recover from this problem?

        • Hey, Donna!

          Bummer. What kind of weeds are we talking here? If it’s annual weeds they’re probably dying out now anyway, so I might try to dethatch and overseed in the spring. If you’re not philosophically opposed, I’d recommend using this Scotts product (Amazon link) in the spring when you overseed. It’s a great quick-release starter fertilizer that includes a pre-emergent that does a nice job blocking weeds. It’s one of the best ones I’ve used that stops the weeds but allows new grass seed to germinate.

          If you take this approach you’ll clean out the old dead stuff from this year, fill in those bare patches with fresh grass in the spring, and make sure your young grass isn’t competing with weeds. About 4-5 weeks after your new seed has germinated spread some corn gluten as a follow-up organic pre-emergent to delay weed growth further.

          If it was my lawn that’s what I’d do – good luck!

  3. Charles K

    Can i take a picture of an invasive weed grass that is taking over my lawn.
    I need it identified then perhaps a remedy to help me eliminate it.
    Thank you

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