7 Best Fertilizers for Grass Seed in 2023

Fertilizing grass seeds is crucial whether you are overseeding or planting fresh grass seeds on a barren patch. It is extremely frustrating to see new grass seeds sprout and then die. Although it is not only a lack of fertilization that can cause grass seeds to die, the importance of proper fertilization cannot be overstated.

There are many fertilizers on the market, but no one-size-fits-all-lawns rule exists. One lawn’s needs will differ from another’s, so selecting a fertilizer based on your lawn’s needs is critical.

Starting fertilizers are the best type of fertilizer for grass seeds. Starter lawn fertilizer aids in rapidly establishing grass seeds and roots in the soil. In addition, these fertilizers contain a fair amount of nitrogen, phosphorous, and potassium, making them perfect for feeding new grass seedlings.

Also Read: 8 Best Grass Seed For Overseeding {Updated 2023}

A variety of fertilizers can be used to feed newly planted grass seeds. And this post will list the top 7 fertilizers for grass seeds in 2023. The fertilizers listed below provide quality products at affordable prices and are suitable for most lawns. So here’s the lowdown on the seven best fertilizers for grass seeds available today.

7 Best Fertilizers for Grass Seed in 2023

Image Product
Scotts Turf Builder Starter Food for New Grass
  • NKP ratio- 24-25-4
  • Grows new grass 70% thicker
  • Enhances seeding outcomes
Scotts Turf Builder Lawn Food
  • NPK ratio- 32-0-4
  • All-season type fertilizer
  • Phosphate-free
Milorganite 32 lb. Slow-Release Nitrogen Fertilizer
  • NPK ratio- 6-4-0
  • Potassium-free
  • Eco-friendly
Scotts Natural Lawn Food
  • NPK ratio- 1-2-2
  • OMRI listed
  • Safe to be used near humans and pets
GreenView 2129193 Fairway Formula Spring Fertilizer Weed & Feed
  • NPK ratio 24-0-6
  • Both fast and slow-release
  • It kills 200+ tough lawn weeds
Jonathan Green & Sons Inc (12414) Winter Survival Fall Fertilizer
  • NPK ratio- 10-0-20
  • Ideal for seeding in the fall
  • No phosphate-formula
Scotts Turf Builder Triple Action Built For Seeding
  • NPK ratio- 21-22-4
  • Kills garden weeds
  • It comes with a triple-action formula

If you look around the market, you will find a plethora of fertilizers for grass lawns (such as Ironite). However, not all of them apply to every grass lawn type. It is also natural to feel overwhelmed by the abundance of options available.

As a result, to assist you, we have listed the top 7 fertilizers that we like that will aid in the growth of new grass seeds and make for a killer lawn.

1. Scotts Turf Builder Starter Food for New Grass

The Scotts Turf Builder Starter is the best product on our list. With an NKP ratio of 24-25-4, this is a starter or quick-release fertilizer. Scotts is a very well-known lawn care brand, and its starter fertilizers are ideal for newly planted grass, sods, and grass plugs. In addition, this product contains a high concentration of nitrogen and phosphorus, which helps grass grow 70% thicker and 35% faster. In other words, this fertilizer is extremely effective at making grass greener and denser.

Furthermore, it is a safe product for reseeding an established lawn and planting a new one. With a 3-pound bag, you can cover an area of 1000 square feet. Although this product does not necessitate watering, it is vital to keep the soil hydrated until the seedlings reach 2 inches.

Pros and Cons of Scotts Turf Builder Starter Food for New Grass


  • Quick-release fertilizer
  • High concentration of nitrogen and phosphorus for better grass growth
  • Safe for all types of grass
  • It does not adversely affect the soil pH
  • Works fast
  • Value for money


  • Not available in Florida
  • Over usage would burn the grass

The Scotts Turf Builder Starter is an effective fast-releasing or starter fertilizer for your grass seed. The product contains an ideal NPK combination that promotes faster and denser grass growth. This fertilizer can also be used safely on any grass, making it extremely versatile.


2. Scotts Turf Builder Lawn Food

Scotts Turf Builder Lawn Food is yet another product on our list. This product will boost your lawn’s nitrogen, promoting rapid grass growth and green coloration. The highlight of this product, according to the company, is that it will not burn your grass if applied properly.

This product can be used on any type of grass at any time of year during the growth phase. It would allow for grass greening as well as the development of deeper grassroots. Overall, this Scotts fertilizer would improve the quality of your lawn by increasing its absorbing capacity and making it nutrient-rich.

You can cover a 5000-square-foot lawn with a 12.5-pound bag. This product’s main purpose is to plump up the lawn and safeguard it from future issues. It has an NPK ratio of 32-0-4.

Note: Please remember that this product contains a lot of nitrogen. As a result, precautions should be taken to avoid burning and killing patches.

Pros and Cons of Scotts Turf Builder Lawn Food


  • Grows grass quickly
  • It makes the lawn denser
  • It is free of the chemical weed 
  • Effective


  • Not to be used during the winter months
  • Too much application can burn the grass
  • Won’t work if the soil is phosphorus deficient

3. Milorganite 32 lb. Slow-Release Nitrogen Fertilizer

We are listing a slow-release fertilizer for grass seed, which is the polar opposite of starter fertilizer. This fertilizer has an NPK ratio of 6-4-0 and can feed for up to 3 months.

One of the main reasons we included this product on our list is that it is environmentally friendly. This claim is mentioned on the packaging. But why is it eco-friendly? Because it remains in the root system rather than getting soaked into the ground. So, this product is suitable for environmentally conscious gardeners. As a result, we can conclude that the Milorganite Slow-Release Nitrogen Fertilizer does not pollute groundwater.

The product has a very low nitrogen content, ensuring that your grass does not burn out. On the other hand, it contains non-staining iron, which will make your grass greener and encourage healthy root formation. Furthermore, the NO salt formula will not dehydrate your lawn soil. 

However, since it is a slow-releasing fertilizer, it may not be very useful to jump-start a lawn from seeds. Nonetheless, it will feed the seeds for a long time, which is vital for their consistent growth. With a 32-pound bag, you can cover an area of 2500 square feet.

Pros and Cons of Milorganite 32 lb. Slow-Release Nitrogen Fertilizer


  • Won’t burn grass
  • NO salt formula
  • Does not pollute groundwater
  • Long-lasting feeding
  • Contains non-staining iron
  • Affordable


  • Won’t work if the soil is potassium deficient 
  • Not an approved organic fertilizer for grass 
  • Not suitable for jump-starting a lawn from seed

4. Scotts Natural Lawn Food

Scotts Natural Lawn Food is another well-known Scotts product. This is an organic lawn fertilizer on the OMRI list. It would take 10-14 days to produce visible results. 

The advantage of this fertilizer is that there is no post-application waiting period. What does this imply? Humans and pets can walk on it instantly after it has been applied.

This fertilizer is suitable for use on new lawns, either before or after seeding or sodding. The NPK ratio is 1-2-2, and a 29-pound bag can cover an area of 4000 square feet.

Pros and Cons of Scotts Natural Lawn Food


  • Quick to work
  • It can be applied during any season
  • You can apply the product to any grass type
  • Organic product
  • No waiting after application 
  • Won’t burn the lawn


  • It leaves an unpleasant odor
  • Low nitrogen content may not jump-start the grass seed growth
  • Not available in CT, FL, ME, MD, MN, NY, WA, and WI

5. GreenView 2129193 Fairway Formula Spring Fertilizer Weed & Feed

The GreenView 2129193 Fairway Formula is a product that helps jump-start seed growth while killing over 200 widespread lawn weeds. It is a fertilizer that is both fast and slow-release. With an NPK ratio of 24-0-6, it quickly releases nitrogen to start growing grass seeds and then slowly releases nitrogen to feed the seedlings for up to 12 weeks.

This product can also help prevent crabgrass for four weeks after the grass seeds have sprouted. Furthermore, zero phosphorus contributes to the prevention of water pollution. However, because the nitrogen content is high, it is best not to overuse the product, as this can cause the grass patches to burn. With a bag of 36-pound, an area of 10,000 square feet can be covered.

Pros and Cons of GreenView 2129193 Fairway Formula Spring Fertilizer Weed & Feed


  • Kills lawn weeds
  • Formula to feed lawn now and later
  • It doesn’t contain phosphorus 
  • Feeds lawn for up to 12 weeks 
  • Pro-grade 
  • It comes with a money-back guarantee by the company


  • Does not treat soil with phosphorus deficiency
  • Expensive 
  • High-level nitrogen can burn the lawn due to overfertilization
  • It cannot be used on St. Augustinegrass or carpetgrass
  • Not available in AK, CA, and HI

6. Jonathan Green & Sons Inc (12414) Winter Survival Fall Fertilizer

The Jonathan Green & Sons Winter Survival Fall Fertilizer may be your product if you want to feed your lawn from September to November. This fertilizer, with an NPK ratio of 10-0-20, prepares your lawn for winter. In other words, it improves the quality of your lawn to help it endure winter-related stressors such as frost, fungus development, inadequate irrigation, and so on. Additionally, your lawn will recover from the summer damage too. The formula promotes deep root growth in grass seeds throughout the winter, resulting in a greener lawn in the spring.

A 45-pound bag will cover an area of 15000 square feet. And if you live in a region with brutal winters, this fertilizer can be extremely beneficial. In addition, the product is ideal for seeding in the fall.

Pros and Cons of Jonathan Green & Sons Inc (12414) Winter Survival Fall Fertilizer


  • Prepares grass for winter months
  • Promoted rapid root growth
  • It covers a large area
  • Quick greening of grass in spring
  • Good to establish new cool-season lawns from seed 
  • Feed for up to 3 months


  • Not suitable for spring or summer feeding
  • Expensive

7. Scotts Turf Builder Triple Action Built For Seeding

The Turf Builder from Scotts has a triple action formula that helps to accelerate the growth of new grass. It is completely safe to seeds and rapidly establishes a greener, thicker grass cover. When planting new grass, use the product immediately after seeding and before misting or irrigating. With an NPK ratio of 21-22-4, it can be used on a new lawn as well as while reseeding an already established lawn.

Also Read: What’s The Best Lawn Fertilizer Ratio?

This fertilizer, along with feeding the grass seeds, helps prevent the spread of weeds such as dandelion, crabgrass, clover, ground ivy, and others for up to 6 weeks without harming the grass seed. This is an excellent starter fertilizer, especially for spring and warm weather seeding. You can cover 4000 square feet with a 17.2-pound bag.

Pros and Cons of Scotts Turf Builder Triple Action Built For Seeding


  • Feeds and strengthens new seedlings
  • It can be used immediately after seeding
  • Establishes a quicker and thicker grass cover
  • Works with Kentucky bluegrass, tall fescue, perennial ryegrass, and centipede grass


  • Jump-start seed growth
  • Some users complained of burning their lawns 
  • Does not kill existing weeds
  • Not available in FL or CA

What is a Good Fertilizer for Grass Seed?

Seeds require nutrients to germinate, which is why timing the application of a good fertilizer is critical. Fertilizers are of two types: regular or slow-release and starter or fast-release. Starter fertilizers are potentially the best types of fertilizers because they are quick to release and readily available for the seeds to absorb.

A starter fertilizer contains essential nutrients that can enable greater soil health. These fertilizers have different nitrogen (N), phosphorous (P-phosphate), and potassium (K-potash) combinations, abbreviated NPK.

These three components promote soil health and aid in the control of weeds, insects, fungus, and other soil issues. Which fertilizer is best for your grass seeds is determined by the purpose of the fertilizer. And to help you understand it better, here are the specific functions of each principal nutrient:

  • Nitrogen: It encourages grass growth. Nitrogen maintains consistent growth in the appropriate season and the grass’s green color.
  • Phosphorus: This element contributes to proper root development. It is the primary food source for grass seeds.
  • Potassium: It encourages pest resistance, drought tolerance, and winter toughness in grasses.

It is important to note that a well-established lawn does not require a fertilizer with high nitrogen content. On the other hand, fully grown lawns don’t require much potassium or phosphorus. However, new grass seeds would require a fertilizer with an NPK ratio close to 21 – 22 – 4.

When To Fertilize New Grass Seed?

When To Fertilize New Grass Seed

Only choosing the right fertilizer is not sufficient. However, applying it at the right time is key to successfully establishing a healthy grass lawn. 

It is always a good idea to fertilize the lawn with a quick-release fertilizer after preparing the soil and before planting new grass seeds. And the best time to fertilize your lawn with a typical nitrogen-rich fertilizer is 4 to 6 weeks after the grass seeds sprout.

Refrain from reapplying the fertilizer too soon, as doing so will burn the grass. You should wait at least four to six weeks before applying another round of fertilizer.

You May Also Read: Best Time to Plant Grass Seed – Solved!

What To Know Before Fertilizing Your Lawn?

Before getting into the best fertilizers for grass seeds, here are a few precautions to take before applying fertilizer.

  • Conduct a Soil Test

Before selecting a fertilizer for your lawn, the most important thing is to conduct a soil test to see if the soil is deficient in any critical nutrient. Based on the results of this test, you can choose the best fertilizer for your grass seed. A soil test can also be done to analyze the pH of the soil.

  • Clean and Remove Debris

It is critical to clear the area of debris before sowing the seeds. This would remove any impediments to the growth of the new grass. Additionally, ensure that the land is sloppy to eliminate the possibility of water stagnation.

  • Soil Amendment

You can modify the soil to increase aeration and reduce water stagnation. That said, it is strongly advised to amend the soil with a1- 2-inch levels of organic substance.

  • Analyze and Adjust the Soil pH

As previously stated, a soil test would aid in determining the pH level of the soil. Therefore, adjusting the pH level will be the next step to meeting the needs of the grass.

The Takeaway

We hope our discussion of the top 7 fertilizers for grass seeds has given you a better idea of what fertilizers are best for growing grass seeds. According to our research, a starter fertilizer is ideal for kicking the growth of grass seeds. On the other hand, a slow-release nitrogen-infused fertilizer would help the seeds get consistent food for their establishment. You can select the one that best suits your needs and your lawn.

If you’ve ever used fertilizer to feed grass seed, please share your experience with us. We would appreciate hearing from you.

About Jennifer Igra

Growing up in Brooklyn, New York City known for it’s green gardens. Jennifer, a 30 year old gardener and green living fanatic started Igra World to share her gardening journey and increase gardening awareness among masses. Follow Igra World to improve your gardening skills.

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