--- title: "We Tested Organic Lawn Fertilizers—These 6 Work Best" description: "Feed your yard one of the best organic lawn fertilizers for green grass that resists disease and pests. See how top picks did in our tests." date: "2026-06-23" modified: "2026-06-23" authors: - name: "Mark Wolfe" job_title: "Staff Writer" link: "https://www.bobvila.com/authors/mark-wolfe/" - name: "Paul Rankin" job_title: "Contributing Writer & Editor" link: "https://www.bobvila.com/authors/paul-rankin/" url: "https://www.bobvila.com/reviews/best-organic-lawn-fertilizers/" categories: - "DIY" - "Lawn & Garden" - "Lawn Care" - "Lawn Care & Gardening" - "Lawn, Garden & Pool" - "Reviews" tags: - "Commerce" - "MPR" --- # We Tested Organic Lawn Fertilizers—These 6 Work Best ![A group of the Best Organic Lawn Fertilizers together on a lawn before testing]() *Photo: Paul Rankin for BobVila.com* Organic fertilizers for lawn grass play a key role in building a thicker, greener lawn without relying on synthetic chemicals, and they’re especially appealing if you’re looking to improve soil health over time. To find the most effective options, we tested six popular fertilizers on a St. Augustine lawn in Florida, applying each to separate sections and tracking changes in color, thickness, and overall growth over several weeks. Across the board, the granular fertilizers delivered the most noticeable results, producing deeper green color and fuller turf compared to untreated areas. Our top pick, the [Lawnbox Grass Genie 10-0-6 from Lawn Box](), stood out for how quickly it improved both color and density without any signs of burning or uneven growth. While most of the granular formulas performed similarly, subtle differences in application, consistency, and long-term results helped separate the best from the rest. The only outlier was the liquid kelp formula, which didn’t give us the same quick visible improvements during testing. (This is likely because it contained zero nitrogen—which St Augustine grass typically wants most—so we can’t judge too harshly there). Choosing a high-quality organic grass fertilizer matters because it directly impacts not just how your [lawn looks](), but how well it holds up over time. Ingredients, nutrient balance, and release speed all play a role in achieving consistent growth without damaging your grass. Ahead, you’ll find our detailed reviews of each product, including how they performed in real-world testing and where each one stands out. ## - **Top Pick: Lawnbox Grass Genie 10-0-6.** Delivers quick improvement in color and density without burning or uneven growth. - **Granular fertilizers outperform liquid options.** Granular formulas showed better results in color and thickness compared to liquid kelp. - **Richlawn 5-3-2 offers great value.** Budget-friendly option with solid performance and safe for various conditions. - **Consider lawn conditions before buying.** Perform a soil test to determine the best organic fertilizer for your lawn's needs. **Bottom line:** Organic fertilizers enhance lawn health and appearance. Choose based on your lawn's specific needs for optimal results. 1. **BEST OVERALL:** [Lawnbox Grass Genie 10-0-6]() [↓ *Jump to Review*](<#lawnbox-grass-genie-10-0-6>) 2. **BEST BANG FOR THE BUCK:** [Richlawn 5-3-2 All-Purpose Lawn Fertilizer]() [↓ *Jump to Review*](<#richlawn-5-3-2-all-purpose-lawn-fertilizer>) 3. **BEST PREMIUM:** [Down to Earth Bio-Turf 8-3-5 All Natural Fertilizer]() [↓ *Jump to Review*](<#down-to-earth-bio-turf-8-3-5-all-natural-fertilizer>) 4. **BEST FOR BEGINNERS:** [Scotts Natural Lawn Food]() [↓ *Jump to Review*](<#scotts-natural-lawn-food>) 5. **BEST YEAR-ROUND:** [Espoma Turf Tone All Season Lawn Food]() [↓ *Jump to Review*](<#espoma-turf-tone-all-season-lawn-food>) 6. **BEST LIQUID:** [GS Plant Foods Organic Liquid Kelp Seaweed Fertilizer]() [↓ *Jump to Review*](<#gs-plant-foods-organic-liquid-kelp-seaweed-fertilizer>) ![A product tester holding a scoop of Lawnbox fertilizer next to its bag and over grass during during testing]() *Photo: Paul Rankin for BobVila.com* ## Quick Comparison: Best Organic Lawn Fertilizers | **Product** | **NPK ratio** | **Quantity** | **Coverage** | **Our Rating** | | --- | --- | --- | --- | --- | | [Lawnbox Grass Genie 10-0-6]() | 10-0-6 | 16 pounds | 2,500 square feet | 5/5 | | [Richlawn 5-3-2 All-Purpose Lawn Fertilizer]() | 5-3-2 | 40 pounds | 4,000 square feet | 4.4/5 | | [Down to Earth Bio-Turf 8-3-5 All Natural Fertilizer]() | 8-3-5 | 25 pounds | 2,000 square feet | 4.5/5 | | [Scotts Natural Lawn Food]() | 11-2-2 | 29.1 pounds | 4,000 square feet | 4.6/5 | | [Espoma Turf Tone All Season Lawn Food]() | 9-0-1 | 28 pounds | 5,000 square feet | 4.7/5 | | [GS Plant Foods Organic Liquid Kelp Seaweed Fertilizer]() | 0-0-1 | 1 gallon | 1,000 square feet | 3.6/5 | ## Before You Buy Organic Lawn Fertilizer Choosing the best organic grass fertilizer requires an understanding of the lawn’s current condition. Is it generally healthy and simply needs regular feeding? Or does it display a nutrient deficiency of some kind? The type of grass will also determine which fertilizer to use. For example, [fertilizers for St. Augustine grass]() will deliver different levels of nutrients than those for [Bermuda grass](). Before buying and applying fertilizer, it’s smart to perform a soil test to identify your soil's pH and nutrient content. These results will help you determine which organic fertilizer to apply as part of your personal [DIY lawn care program](). ## Our Top Picks ![Best organic lawn fertilizers - 3 weeks AFTER]() *Photo: Paul Rankin for BobVila.com* Each organic lawn treatment on our list of top picks is made from quality ingredients and provides essential nutrients for growing [new grass]() or helping an existing lawn thrive. The Grass Genie 10-0-6 earned its top spot by delivering the most noticeable improvement in both color and thickness during testing. This 100 percent organic formula is designed for spring applications, combining quick- and slow-release nitrogen to jump-start growth while continuing to feed the lawn for several weeks. It also includes humic acid to support soil health, which can help improve nutrient absorption over time. The formula is free from animal byproducts and biosolids, making it a cleaner option for homeowners who want a more natural approach to lawn care. In side-by-side testing, we could clearly see that this fertilizer produced the deepest green color and the fullest turf after about a month, which clearly outperformed the other options. Application was straightforward, and like the other granular formulas, it spread evenly without any issues. The only real downside we found is that it’s more of a seasonal product, best suited for spring use rather than year-round feeding. Still, for a strong early-season boost, it stood out as the most effective option overall. Richlawn Organic 5-3-2 is a straightforward, budget-friendly option that still delivers solid results. This OMRI-listed formula is made from 100 percent organic ingredients, with a heavy focus on slow-release nitrogen to provide steady feeding over time. It’s widely used by turf professionals on golf courses and commercial properties, but we found it just as easy to apply at home. The non-burning formula is safe for use on new or established lawns, even in warmer conditions, and we also liked that it can be used on gardens and landscaping beds, too. In testing, it performed right in line with the other granular fertilizers, producing noticeably greener and slightly thicker grass after a few weeks. Application was simple and consistent, with no issues during [spreading](). Where it really stands out is value—it’s one of the most affordable options in the lineup without sacrificing performance. While it doesn’t offer any standout extras compared to higher-end blends, we found it to be a reliable, no-frills choice that gets the job done. Down To Earth Bio-Turf 8-3-5 is a well-rounded organic fertilizer that focuses on both visible growth and long-term lawn health. This granular formula is rich in nitrogen to promote early-season greening, while added potassium helps the grass better handle stress from heat and drought. It’s also designed to support deeper root development, which we found helpful for encouraging thicker and healthier growth over time. The packaging stands out as well, using a thick paper bag instead of plastic, which feels more in line with its natural approach. In testing, this nitrogen-rich lawn fertilizer​ performed just as well as the other top granular options, producing a noticeably greener and fuller lawn after about a month. The granules were easy to spread evenly, making application quick and hassle-free. While it doesn’t dramatically outperform similar formulas, we think it’s a reliable choice with a strong nutrient profile and a more eco-conscious packaging. Scotts Natural Lawn Food is a widely available option that offers a simple, no-fuss way to maintain a healthy lawn throughout the growing season. With an 11-2-2 NPK ratio, it provides a balanced mix of nutrients to support steady growth, root development, and overall lawn resilience. The formula is made from natural ingredients like bone meal and blood meal and is suitable for all grass types. Scotts recommends applying it every 6 to 8 weeks, making it a practical choice for ongoing feeding. When we tested it, it performed pretty similarly to the other granular fertilizers, giving greener, thicker grass within a few weeks. The large bag size and consistent granules made it easy for us to apply evenly using a standard spreader. Coverage is somewhat limited for the bag size, so larger lawns may require multiple bags over the season. Still, its accessibility and ease of use make it a solid pick, especially for homeowners new to organic lawn care. Espoma Turf-Tone All Season Lawn Food is designed to be a reliable, year-round option for maintaining healthy grass across multiple growing conditions. Its 9-0-1 formula relies on slow-release nitrogen to promote steady growth and long-lasting color, while the brand’s Bio-tone blend is intended to support soil health and root development. It’s safe for use on a wide range of grass types, including St. Augustine and [zoysia](), and is made without sludges or harsh chemicals, making it a solid choice for households with kids and pets. It performed similarly to the other granular fertilizers we tested, producing a greener, thicker lawn after roughly 2 weeks. The granules spread easily and evenly, making application straightforward with a standard spreader. While we didn’t feel like it stood out dramatically compared to the top performer, its all-season versatility makes it a dependable option for ongoing lawn care rather than a one-time boost. GS Plant Foods Organic Liquid Kelp Fertilizer takes a different approach from the granular options, using seaweed extract (*Ascophyllum nodosum*) to support overall plant health rather than delivering a heavy dose of nutrients. With a very low NPK ratio (0-0-1), it’s better suited as a supplement or soil conditioner than a primary lawn fertilizer. The liquid formula must be diluted with water and applied using a sprayer, which adds an extra step compared to traditional spread-and-go products. On the plus side, it has little to no odor and can be used across a wide range of plants, from lawns to garden beds and even houseplants. On our test lawn, we didn’t notice this organic liquid lawn fertilizer​ producing the same instant improvement in lawn color or thickness as the granular fertilizers, especially on St. Augustine grass, which tends to respond best to nitrogen-rich formulas. Our treated patch stayed sparse and less green compared to the others. However, its versatility makes it a useful option for gardeners looking to support overall plant health rather than maximize lawn growth. ## Or, DIY Your Own Organic Lawn Fertilizer While there are plenty of commercially produced organic lawn fertilizers on the market, it’s also possible to make a [homemade fertilizer for lawns]() that delivers excellent results. A good fertilizer for grass should be about 50 percent organic matter and plant-based material, such as composted manure, garden clippings, decomposed leaves, sphagnum peat moss, sawdust, wood chips, or even seaweed. The other half of the fertilizer blend should contain slow-release sources of nitrogen such as blood meal, fish meal, cottonseed meal, feather meal, kelp meal, or soybean meal. Once you have gathered the necessary materials for the homemade lawn fertilizer mix, start blending them in equal parts in a bucket or large container. Make sure to mix them thoroughly so it's easy to apply everything evenly on your lawn. ## [Jump to Our Top Picks](<#recap>) ![Best organic lawn fertilizers - application]() *Photo: Paul Rankin for BobVila.com* ## FAQs The [best organic fertilizer]() can help keep lawns vigorous and healthy. For more information on using fertilizers, check out the answers to these frequently asked questions. ## Author Mark Wolfe is a BobVila.com staff writer with an extensive background in the horticulture industry. Since 2020, he has contributed numerous gardening and home improvement articles, along with a variety of tool and product reviews.