The 9 Best Organic Lawn Fertilizers of 2024

Best Overall

Dr. Earth Super Natural Organic Fertilizer

View On Walmart $58 View On Home Depot

The best fertilizer for your grass will depend highly on how acidic or alkaline your soil is, but there are a few key nutrients that most yards will benefit from: nitrogen, phosphorus, and potassium. The Dr. Earth Super Natural Organic Fertilizer includes all three of these nutrients, but unlike synthetic fertilizers, this organic fertilizer is made with all-natural ingredients.

According to the manufacturer, its ingredients are sourced from land and ocean plants, fish bones, and mined minerals, which are non-harmful to both pets and humans. This means you don't have to stay off the lawn after applying fertilizer.

The nitrogen in this fertilizer encourages steady growth and allows your grass to achieve a rich green color, while potassium activates enzymes to help the grass grow and protect it against extreme temperatures. Phosphorus transfers energy throughout the plant, making it especially important in new grass.

Plus, the Dr. Earth Super Natural Organic fertilizer releases its nutrients into the earth more slowly than a synthetic fertilizer, which creates more long-term results. This allows your grass to grow at a more consistent rate, create stronger root systems, and go through less stress.

It's important to note that because this fertilizer contains phosphorus—a nutrient that can contaminate local water sources—you'll need to be careful to follow the directions when applying it to your lawn. This helps to ensure that the phosphorus gets properly absorbed and doesn't run off.

Product Details: Fertilizer Analysis (N-P-K): 9-3-5 | Recommended Use: Spring to summer | Package Size: 18 pounds | Yard Size: Up to 2,000 square feet

Best for Fall

Espoma Fall Lawn Booster

View On Amazon $56 View On Walmart $56 View On HorseloverZ.com

As the seasons change from summer to fall, you're probably thinking less about your grass and more about other outdoor chores like raking leaves or prepping your plants for the first frost. However, autumn is a great time to apply fertilizer because it can help ensure your grass has everything it needs to come back strong and healthy next spring.

The Espoma Fall Lawn Booster is the best fertilizer for grass in the fall because it contains a higher percentage of potassium than most spring fertilizers. Potassium helps to fortify your lawn against drought and stressors, such as extreme weather changes and below-freezing temperatures.

This grass fertilizer also contains 8% nitrogen to help your lawn grow thicker and appear more lush next spring. There's also small amounts of sulfur and calcium, which are both secondary nutrients that support soil health and grass growth.

According to the manufacturer, you should apply the Espoma Fall Lawn Booster in September to November on a dry lawn that has just been mowed, then water lightly to help the soil absorb the nutrients.

However, if your yard is made up of warm season grasses like Bermuda grass or St. Augustine grass, you'll likely see more results by using a spring fertilizer instead. Since these grass types experience their most active root growth in spring, applying a fall fertilizer won't be as effective.

Product Details: Fertilizer Analysis (N-P-K): 8-0-5 | Recommended Use: September to November | Package Size: 30 pounds | Yard Size: Up to 5,000 square feet

Best for Spring

Espoma Spring Lawn Booster

View On Amazon $47 View On Walmart $49 View On HorseloverZ.com

Spring is a great time of the year to start fertilizing your yard, especially if you've noticed that your lawn has a difficult time bouncing back after a long, cold winter. It's important to wait until at least May to begin adding fertilizer since your grass needs to put all of its energy on root development in early spring.

The Espoma Spring Lawn Booster contains 2.5 times more slow release nitrogen than conventional lawn programs, which is a critical nutrient when it comes to growing healthy, green grass. Lawns with the right balance of nitrogen will be able to photosynthesize better and grow thicker and stronger blades of grass.

This spring lawn fertilizer also includes 3% calcium, which can help strengthen the grass against disease that could stunt growth or kill the grass. Since the Espoma Spring Lawn Booster is a slow-release fertilizer, it gives your grass small, steady amounts of nutrients at a time to promote the long-term wellbeing of your yard instead of dramatic, short-lived results.

If your soil test shows that your yard is alkaline (a pH higher than 7.5), you'll likely want to skip this organic grass fertilizer. Highly alkaline soils tend to possess a high amount of calcium to begin with, and adding more calcium can inhibit your grass's ability to absorb other nutrients.

Product Details: Fertilizer Analysis (N-P-K): 8-0-0 | Recommended Use: February to April | Package Size: 30 pounds | Yard Size: Up to 5,000 square feet

Best Slow-Release

Milorganite Slow-Release Nitrogen Fertilizer

View On Walmart $65 View On Home Depot View On Ace Hardware $25

Slow-release fertilizers are the best fertilizers for grass because they gradually release nutrients into your soil instead of all at once. While this means it takes a bit longer to see results in your yard, the slower process ensures that the maximum amount of nutrients gets absorbed into your soil instead of running off.

The Milorganite organic nitrogen fertilizer is a great option for grass that is yellowing, grows slowly, or is susceptible to weeds. Unlike synthetic fertilizers that derive nitrogen from harmful sources, the nitrogen in Milorganite grass fertilizer is derived from natural sources.

If your yard typically turns yellow or brown in spring and summer, the Milorganite organic nitrogen fertilizer also includes iron in its list of ingredients to help restore your grass to a rich, green color. It also contains calcium, another essential plant micronutrient that helps encourage growth.

Product Details: Fertilizer Analysis (N-P-K): 6-4-0 | Recommended Use: Year round | Package Size: 32 pounds | Yard Size: Up to 2,500 square feet

Best High-Nitrogen

Purely Organic Products Grub & Feed Lawn Food

View On Home Depot $34

Applying a high-nitrogen fertilizer can help promote steady growth and keep your grass a healthy green hue instead of withering in the heat. The Purely Organic Products Grub & Feed Lawn Food fertilizer contains a high concentration of nitrogen. This is a crucial nutrient that helps your grass produce chlorophyll and transform sunlight into energy.

By applying a high-nitrogen fertilizer while your grass is in the middle of its growing season, you'll be able to provide it with the proper nutrients to create thick, lush blades of grass. The Purely Organic Products fertilizer also contains potassium, which is responsible for healthy development of your lawn's roots.

Instead of using synthetic substances to feed your yard, though, this fertilizer is derived from corn gluten meal, urea, and potassium acetate—all natural ingredients. It also includes botanical oils to prevent grubs or other pests in the soil.

The manufacturer recommends applying this fertilizer on a day when no heavy rains are expected, then lightly watering your lawn to activate the fertilizer. Keep in mind that because this is a high-nitrogen fertilizer, you want to avoid over-applying it to your yard. Too much of this type of fertilizer can increase the nitrogen and salt levels, which may damage your grass.

Product Details: Fertilizer Analysis (N-P-K): 10-0-2 | Recommended Use: July to August | Package Size: 15 pounds | Yard Size: Up to 3,000 square feet

Best for Bermuda Grass

Safer Brand Lawn Restore Natural Lawn Fertilizer

View On Amazon $42 View On Walmart $42 View On Home Depot $41

Bermuda grass is a popular lawn grass because of its durability against extreme heat and drought conditions. To keep your Bermuda grass looking lush and golf-course green from early spring to late fall, apply a fertilizer with nitrogen and potassium to fuel its growth and further protect it from weather extremes.

The Safer Brand Lawn Restore lawn fertilizer will help both cool- and warm-season grasses withstand stress, develop stronger roots, and grow consistently. If you're noticing that your lawn has bare spots, is yellowing in some areas, or has a lot of weeds popping up throughout the yard, it's possible that stress is the culprit.

Extremely hot or cold weather or long periods without rain can cause your grass's roots to shrink, making it more susceptible to weeds, disease, and insects. However, the best fertilizers for grass supply easy-to-absorb nutrients to stressed lawns.

To combat these issues, the Safer Brand fertilizer includes nitrogen to encourage chlorophyll production and potassium for helping the grass resist drought and disease. This means that, even though you can't control the weather in your neighborhood, you'll be able to better protect your yard from the consequences of a hot, dry summer.

While this grass fertilizer produces quick results—the manufacturer says to expect greener grass in three to five days—it needs to be reapplied more often than other fertilizers. Plan to add more fertilizer after eight weeks to maintain your lawn.

Product Details: Fertilizer Analysis (N-P-K): 9-0-2 | Recommended Use: All seasons | Package Size: 20 pounds | Yard Size: Up to 5,000 square feet

Best Liquid

Bare Ground Fish Fertilizer

View On Amazon $12 View On Walmart $19 View On Lowe's $22

Fish fertilizer is made from parts of the fish carcass (bones, scales, and skin) that would otherwise go to waste. The idea of fish fertilizer may sound strange, but it can improve soil health and add nitrogen, phosphorus, and potassium just as synthetic fertilizer formulas do.

This liquid fish fertilizer has a 2-3-1 NPK ratio and increases antioxidants, beneficial microbes, and the number of earthworms in the soil. The increased soil microbes can help decrease the need for pesticides too, allowing for a more organic approach to gardening. This all-natural cold-pressed formula can be used on all types of lawns, as well as fruit and vegetable plants. It’s OMRI-Listed as safe for organic gardening. 

Trident’s Pride fertilizer comes in an easy-to-pour jug—simply dilute the formula with water before applying to your grass or other plants. The company recommends using 4-6 ounces per gallon of water, so 1 gallon will last you for quite a while.

As you might expect, it does have a fishy smell, but it goes away quickly if the product is diluted with water as recommended. 

Product Details: Fertilizer Analysis (N-P-K): 2-3-1 | Recommended Use: Spring, summer, fall | Package Size: 1 gallon | Yard Size: Not listed

Best for Centipede Grass

The Andersons Organic Fertilizer

View On Amazon $83 View On Home Depot $78 View On Andersonshomeandgarden.com

Centipede grass is well suited for Southern areas of the United States and is relatively low maintenance, but regular fertilizer applications can help it look its best. Just be sure not to over apply fertilizer (as centipede grass doesn’t need too much fertilizer) and choose a fertilizer with low levels or no phosphate.

Innova Organic Ferilizer is a slow-release formula that will help you ensure you don’t burn the centipede grass by applying too much fertilizer at once since the nutrients in the fertilizer will slowly be released over time. This product can also be applied in hot/dry weather, which makes it ideal for Southern regions where centipede grass thrives. 

Innova Organic Fertilizer can be used on all types of grass and is OMRI-listed as safe for organic gardening. Unlike many other fertilizers, you won’t notice a strong smell when you apply it and it’s safe to use where kids and pets play. It’s made from plants and doesn’t include any manure, animal parts, or other composted waste products. It also supplies carbon to the soil to help introduce beneficial soil microbes and improve soil health. 

This fertilizer can be used on any grass type and is best applied in spring through fall. It works well for establishing new lawns and restoring lawns that have seen better days. Centipede grass doesn’t need much phosphorus, so do a soil test to check on existing phosphorus levels in the soil if you want to use a fertilizer with phosphorus on a regular basis. 

Product Details: Fertilizer Analysis (N-P-K): 7-1-2 | Recommended Use: Spring, summer, or fall | Package Size: 40 pounds | Yard Size: Up to 11,000 square feet