Creating a lush, healthy lawn requires attention to key details like mowing, irrigation, and plant nutrition. Mowing is a simple matter of keeping the blade sharp and setting the proper height. Similarly, irrigation is pretty straightforward once you understand the basics of deep, infrequent watering. Plant nutrition, on the other hand, can get a bit complicated.
Although the basics of what makes grass grow are common from yard to yard, factors like soil acidity, grass type, and time of year necessitate a more nuanced approach to fertilizers. That’s why there are so many fertilizer options out there.
With that in mind, continue reading to discover some top factors to consider when choosing one of these products and explore reviews of some of the best organic lawn fertilizers for healthy lawn care.
- BEST OVERALL: The Andersons 7-1-2 Innova Organic Fertilizer
- BEST BANG FOR THE BUCK: Jonathan Green (10250) Organic Lawn Food
- BEST FOR P & K DEFICIENCY: Scotts Natural Lawn Food
- BEST FOR N DEFICIENCY: Urban Farm Fertilizers Liquid Lawn Fertilizer
- BEST WITH NO PHOSPHORUS: Espoma EOLB30 Organic Lawn Booster Fertilizer
- BEST FOR DARK-GREEN LAWN: Milorganite 0636 Organic Nitrogen Fertilizer
- BEST FOR FALL: Espoma EOFW30 Organic Fall Fertilizer
- BEST ORGANIC LIQUID: GS Plant Foods Organic Kelp Fertilizer
Before You Buy Organic Lawn Fertilizer
Choosing the best organic lawn 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 the best kind of fertilizer to use. For example, St. Augustine grass has different nutritional needs than Bermuda grass or zoysia grass.
Before buying and applying fertilizer, it’s highly recommended to perform a soil test to identify the soil pH and nutrient content. Use these test results to help determine which fertilizer is the best fit.
How We Chose the Best Organic Lawn Fertilizers
Years of experience covering home and garden products as well as extensive product research went into creating this guide. We explored more than 20 fertilizer options and weighed a number of practical considerations before making our recommendations.
- Organic vs. inorganic: We only considered organic fertilizers for this guide since they are capable of top-notch performance without negative environmental impact.
- NPK ratio: Since different lawns have unique needs in terms of macronutrients, we included formulations with a variety of different NPK (nitrogen/phosphorus/potassium) ratios.
- Value: Plant fertilizers vary widely in type and quantity. We ensured that each recommended product offered excellent value, regardless of the format.
Our Top Picks
To qualify as a top pick, an organic lawn fertilizer is made from quality ingredients and provides the proper nutrients to grow healthy grass. The following products are suitable for a broad range of applications and have a proven track record for maintaining robust lawns.
Innova organic fertilizer packs a 7-1-2 NPK ratio and amino acids in a slow-release formula for regular lawn maintenance. It contains no biosolids, manure, composted waste products, or animal parts. The low amount of dust granules make for easy application without causing coughing and sneezing.
The nonburning formula prevents damage from overapplication, and it’s safe to use adjacent to sensitive waterways. This is an excellent all-around lawn food for all types of grass. The 40-pound bag feeds up to 5,600 square feet.
- NPK ratio: 7-1-2
- Quantity: 40 pounds
- Coverage: 5,600 square feet
- Low quantity of dust granules makes this product easier to apply
- Versatile formula is suitable for many different types of grass
- Suitable for beginners because of its nonburning formula
- This product is not readily available from all major retailers
- 40 pounds may be a larger quantity than some users need
Get The Andersons organic lawn fertilizer at Amazon.
Jonathan Green’s organic lawn food is a granular fertilizer made with a complex of plant and animal proteins, including feather meal, soybean meal, molasses, and wheat middlings. The 10-0-1 NPK formula delivers a boost of nitrogen plus iron to keep the grass growing with a dark-green color for up to 10 weeks. Child and pet traffic are safe immediately after application. The 17-pound bag feeds up to 5,000 square feet.
- NPK ratio: 10-0-1
- Quantity: 17 pounds
- Coverage: 5,000 square feet
- Children and pets can play on the lawn immediately after application
- Each application lasts for up to 10 weeks
- Formulated with a combination of plant- and animal-derived ingredients for added versatility
- This product is not suitable for lawns requiring potassium
Get the Jonathan Green organic lawn fertilizer at Amazon.
New and struggling lawns sometimes require a bit more phosphorus and potassium to boost deep root development and drought tolerance. Scotts natural lawn food offers both, plus a healthy serving of nitrogen, with its 11-2-2 NPK content. It is also excellent for regular lawn maintenance.
The manufacturer recommends feeding up to four times through the growing season at 6- to 8-week intervals. The 29.1-pound bag feeds 4,000 square feet.
- NPK ratio: 11-2-2
- Quantity: 29.1 pounds
- Coverage: 4,000 square feet
- This product is gentle enough to use on freshly seeded or sodded grass
- Provides a balance of phosphorus and potassium along with nitrogen
- The lawn is safe to walk on immediately after fertilizer application
- This product isn’t suitable for larger lawns as it only covers 4,000 square feet
Get the Scotts Natural organic lawn fertilizer at Amazon or The Home Depot.
This super-concentrated liquid fertilizer from Urban Farm Fertilizers boasts 13 percent nitrogen plus iron to help the grass grow and turn deep green at the beginning of spring. Instantly treat nutrient-deficient lawns with an overall 13-1-2 NPK content.
The ingredients in this combination organic fertilizer include bat guano, sea kelp, worm castings, humic acid, hydroponic-grade minerals, and more. For the easiest application, apply with a hose-end sprayer (sold separately). This 1 gallon of concentrate creates 256 gallons of fertilizer, treating 5,000 square feet up to eight times at 3-week intervals.
- NPK ratio: 13-1-2
- Quantity: 1 gallon (makes 256 gallons)
- Coverage: Up to 80,000 square feet
- Concentrated formula provides 20,000 to 80,000 square feet of coverage
- Iron in the formula promotes the growth of deep-green grass
- The combination formula includes animal- and plant-based ingredients for optimal performance
- This product must be applied more frequently than slow-release fertilizers at 2 to 3 times per month
Get the Urban Farm Fertilizers organic lawn fertilizer at Amazon or The Urban Farm.
A well-planned organic fertilizer program balances deep greening and healthy growth with limited nutrient application. Espoma’s Organic lawn booster does just that with a moderate dose of slow-release nitrogen and a boost of calcium for improved health. The 8-0-0 NPK analysis is supplemented with 3 percent calcium and 1 percent sulfur. This 30-pound bag feeds 5,000 square feet of lawn.
- NPK ratio: 8-0-0
- Quantity: 30 pounds
- Coverage: 5,000 square feet
- Formula includes calcium and sulfur for improved grass health
- Slow-release formula means less frequent application is needed
- Product promotes disease resistance while making the lawn look better
- This formula isn’t suitable for lawns requiring potassium or phosphorus
Get the Espoma booster organic lawn fertilizer at Amazon.
Milorganite granular fertilizer is an elder among branded organic fertilizers, used by professionals and home gardeners for nearly a century. This organic nitrogen fertilizer is made from nutrient-rich heat-dried microbes that have digested the organic matter in wastewater.
With the creation of a fertilizer program in the early 1900s, the City of Milwaukee was the first municipality to reclaim waste on a massive scale and market it for profit. This is a proven, effective product with a great story about innovation and commitment to a clean environment. The fertilizer’s analysis is 6-4-0, plus a 2.5-percent iron content for deep greening. This 36-pound bag feeds 2,500 square feet.
- NPK ratio: 6-4-0
- Quantity: 36 pounds
- Coverage: 2,500 square feet
- Formula is fortified with iron for a dark-green lawn
- Brand has a long history of top-notch performance
- Fertilizer provides both nitrogen and phosphorus
- This product provides a limited coverage area of 2,500 square feet, so it’s not suitable for larger yards
Get the Milorganite organic lawn fertilizer at Amazon or Lowe’s.
Looking for a way to prep a lawn for winter? This fertilizer from Espoma is designed to be used at the end of the summer season, between September and November, and ensures that the grass remains healthy during the dormant season.
With an NPK ratio of 8-0-5, this formula is rich in nitrogen and potassium but lacks phosphorus. The nonburning formula ensures that overfertilization isn’t an issue. The product is suitable for all lawn types, including lawns that have recently been seeded or sodded. It is, however, best to apply this product to a dry lawn that has recently been mowed.
- NPK ratio: 8-0-5
- Quantity: 30 pounds
- Coverage: 5,000 square feet
- This fertilizer is specifically formulated for winterizing lawns
- Suitable for all lawn types, including lawns that have recently been seeded or sodded.
- Features a nonburning formula so users needn’t worry about overfertilization
- This formula doesn’t contain any phosphorus, so it may not be suitable for some lawns
Get the Espoma fall organic lawn fertilizer at Amazon.
This organic kelp fertilizer from GS Plant Foods is dependent on one hero ingredient: ascophyllum nodosum extract. This seaweed fortifies plants of all types, making this fertilizer not only suitable for lawns but also flower beds, vegetable gardens, and houseplants. It can even be used to extend the life of cut flowers.
The product comes in a 1-gallon bottle and is designed to be diluted with water at a ratio of 1 ounce of fertilizer to 1 gallon of water. The NPK ratio is 0.3-0-0.6, so nutrient levels are low, allowing this product to be combined with other types of fertilizers if desired.
- NPK ratio: 0.3-0-0.6
- Quantity: 1 gallon
- Coverage: 1,000 square feet
- Concentrated formula is designed to be mixed with water for higher coverage
- This product is suitable for both indoor and outdoor plants
- Can be combined with other fertilizers for enhanced performance
- The coverage area is low compared to other top products
- Lack of phosphorus and low concentrations of nitrogen and potassium may limit its usefulness
Get the GS Plant Foods organic lawn fertilizer at Amazon.
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 DIY your own homemade fertilizer to achieve the best results. When making a fertilizer, the organic matter should make up about 50 percent of the mixture. This can include plant-based material such as composted manure or garden clippings, decomposed leaves, sphagnum peat moss, sawdust or wood chips, or even seaweed. The other half of the fertilizer blend should be made up of 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, it’s time to start blending them together in a bucket or large container. Start by adding one part of organic matter to one part of the slow-release nitrogen source until all materials are thoroughly blended together. It’s important to make sure everything has been evenly distributed while mixing so that it will be evenly spread when applied onto the lawn.
We recommend The Andersons organic lawn fertilizer for its versatility, organic formulation, and availability. There are other common lawn fertilizer options, including Scotts Turf Builder, Pennington UltraGreen Weed & Feed, and Spectracide Weed & Feed. However, they do not meet our sustainability guidelines and are not recommended in our top picks due to their potentially harmful ingredients and negative impact on the environment.
What to Consider When Choosing the Best Organic Lawn Fertilizer
In addition to nutrient requirements revealed through soil test results, consider several important factors before deciding on the best organic lawn fertilizer for a yard. Read on to learn more about the types of organic fertilizer, the form in which it’s applied, the all-important NPK ratio, and the desired effect.
Organic fertilizer ingredients fall into three types: animal-based, plant-based, and mineral-based. However, most products contain a combination of these types to deliver the best possible balance of major and minor nutrients. Some products may only offer a single ingredient or a blend of ingredients from a single type.
Animal-based fertilizers include blood meal, bone meal, feather meal, fish meal, and various manures. These products slowly break down over time, providing lawns and garden plants with season-long benefits.
Plant-based fertilizer ingredients include alfalfa meal, cottonseed meal, kelp meal, soybean meal, and compost. Soil microbes convert these materials into plant food much more quickly than animal products. They provide an immediate impact, often within days or weeks after application.
Mineral-based fertilizer ingredients like sulfur, dolomitic limestone, gypsum, greensand, and rock phosphate are naturally occurring concentrated forms of plant-food elements. They boost trace nutrient levels and eliminate deficiencies in the soil.
Liquid vs. Granular
Organic fertilizers, both liquid and granular, work with the naturally occurring microbes in the soil. When the fertilizer is applied to the soil, bacteria and fungi consume the natural ingredients and release the nutrients at a measured rate and in a form that is readily available to plants.
The difference between liquid and dry organic fertilizers is in the rate at which the soil consumes them. Dry granular formulations break down slowly, feeding the lawn over the course of months. Liquid organic fertilizers work faster due to the minute particle size and available moisture. Choose liquid fertilizer for a quick boost of nutrients.
There are three elements that make up the major nutrients that lawns and plants need for lush, green growth.
- Nitrogen (N) promotes green color and leafy growth.
- Phosphorus (P) stimulates deep root development.
- Potassium (K) boosts vigor and disease resistance.
Nitrogen is quite volatile. The amount not used by the lawn dissipates and must be regularly replenished. Phosphorus and potassium persist in the soil, so they are not required in such large quantities. On average, organic lawn fertilizer offers two to three times or more N compared to the amounts of P and K in the mix.
Locate the NPK ratio on the fertilizer label. It shows the amount of each element present in the product as a percentage of the total weight, always in the order N-P-K. For instance, a product with a ratio of 11-2-2 contains 11 percent N, 2 percent P, and 2 percent K. Other ingredients and any additional nutrients may also be present elsewhere on the label.
After a soil test, it’s essential to factor the condition of the lawn into the fertilizer choice. If the grass is robust with dense foliage and deep green color, choose a fertilizer with a moderate to high amount of N (10 percent or greater) and little to no P and K. In late summer and fall, as the lawn approaches the dormant season, apply fertilizer with a lower N ratio and slightly more K.
Sometimes the lawn may appear yellow even when the three major nutrients are properly supplied. This is a common symptom of iron deficiency. For a deeper green, choose a lawn fertilizer with supplemental iron.
Phosphorus is already sufficiently present in the soil in many areas, and it may be highly regulated to prevent pollution.
Tips for Using Organic Lawn Fertilizer
There’s more to an effective organic lawn fertility program than simply applying fertilizer on a timed schedule. Don’t waste time and money by blindly applying fertilizer. First, test the soil, either with an over-the-counter testing kit from a local garden center or by sending a sample to the state’s Cooperative Extension Service for analysis. Then, use the results to map out a plan of action.
The first step should be to adjust the pH of the soil as indicated by test results. Establish the proper soil pH, between 5.8 and 7.2 depending on the grass species, to ensure that the grass can efficiently pull nutrients out of the soil. Lime raises the pH, while sulfur and aluminum sulfate lower it. Once the acidity is ideal, proceed with the necessary fertilizer application—and remember to mulch grass clippings.
- Use soil test results to determine fertility needs.
- Apply lime as necessary to maintain the proper soil pH and maximize fertilizer efficiency.
- Mulch grass clippings and leave them on the lawn to reduce fertilizer requirements by as much as 30 percent.
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.
Q. How do I know what fertilizer to use on my lawn?
Before purchasing a fertilizer, buy an over-the-counter soil test kit, or send a soil sample to your county’s Cooperative Extension Service for analysis. Use the soil test results to guide fertilizer applications.
Q. When should I apply fertilizer to my lawn?
Grass will take up fertilizer throughout the growing season. The best times to apply it are when active growth begins in spring and again in midsummer.
Q. How much organic lawn fertilizer can I use?
While organics are typically labeled as “nonburning,” excess fertilizer is a source of pollution. Follow soil test results and the instructions on the label of the specific product you are using.
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