Fertilizing New Sod: Establishing a Strong Foundation

By: Ken Wilson

New sod is at its most volatile when it is initially establishing roots. Whether a roll-on (pre-grown) or seeded lawn, new grass establishes the best foundation with a little extra effort from the planter. How do we fertilize new sod?

Establish a strong foundation for new sod by applying a starter fertilizer. Starters have a high phosphorus ratio, encouraging healthy plant development and providing fast root growth. Without proper macronutrients, seeds and sod are prone to environmental stress, disease, and poor installation.

Growing grass in a previously barren area or regrowing after a challenging growing season, like winter, is tricky, especially when unsure of the soil quality. Introducing fertilizer at the correct time can make or break a thriving turf.

What Fertilizer to Use on New Sods

The more nutritious your soil, the better. A new lawn often gets built on previously damaged growing areas, and reintroducing nutrients is integral to prepping the area for new growth. Fertilizers used for established lawns will likely not meet the nutritional needs of new sod, such as a higher nitrogen and phosphorus ratio.

An NPK ratio (nitrogen-phosphorus-potassium) of 20-10-10 or 5-10-5 is ideal for new lawns. The goal of starter fertilizer is to establish fast and deep root growth to assist grass in facing weather conditions and foot traffic. Testing your soil beforehand can assist you in choosing the correct fertilizer based on which macronutrients are lacking.

Best Fertilizer For New Lawn

Choosing the correct starter fertilizer for establishing new sod relies on the macronutrient ratio, ease of use, safety, and release type. Fertilizers can be fast or slow-releasing and come as liquids, granules, and raw products from local farms (organic material). Slow-release fertilizers are better for seeding and soil tilling. At the same time, fast-release is better for application on top of sod as it minimizes burning.

Best fertilizer for new lawn top picks:

FertilizerCoverage per Sq. Ft.NPK RatioFertilizer FormSafe for use around pets/childrenSlow or fast release
Scotts, Turf Builder Starer Food3lb. bag covers 1,000 sq24-25-4GranulesYesFast
Jonathan Green, Green Up Seeding And Sodding5lb. bag covers 1,500 sq12-18-8 plus humatesGranulesYesSlow
Ferilome, New Lawn Starter Fertilizer4lb. covers 1,000 sq9-13-7 with boron, iron, and copperGranulesYesFast
The Andersons, Premium New Lawn Starter Fertilizer18lb. bag covers 5,000 sq20-27-5 plus Iron and SulfurGranulesYesSlow and fast
Greenview, Starter Fertilizer7lb. covers 2,500 sq10-18-10GranulesYesSlow and fast

Even if a fertilizer is safe for pets and children, it is best to be cautious and wait at least 12 hours after the initial watering of the product or until the lawn is dry before allowing pets or children onto the lawn.

1. Scotts, Turf Builder Starter Food

Scotts is well-praised for its fertilizers, and its Turf Builder Starter Food is no exception. Apply their lawn starter before or after seeding or installing sod. It is suitable for all lawn types and helps establish new sod faster and thicker. Scotts’ turf builder is the best client rated grass starter food on this list.

Water this fertilizer lightly after application and keep the soil moist daily. Be sure not to apply before heavy rains, as phosphorus can be dangerous when washed down drains.

Reviewer’s comments:

  • Pros: It is very effective for germinating new seedlings and adding plugs to barren patches in the garden.
  • Cons: The product is prone to clumping when exposed to moisture, so you must always carefully seal the bags.

2. Jonathan Green, Green Up Seeding and Sodding

This organic fertilizer, made by Jonathan Green, is excellent for same-day application. When installing new sod or seed, Green Up Seeding and Sodding should be applied the same day. It’s effective for use in spring until fall and should be applied to dry lawns and watered after application.

This plant food includes humates, which accelerate plant activity and growth. Humates, coupled with the high phosphorus, make Green Up a strong foundation for establishing roots.

Reviewer’s comments:

  • Pros: This product works well in shaded and sunny areas and shows results within a week of application.
  • Cons: You must remove any stray granules from the paving as it will leave a stain.

3. Ferilome, New Lawn Starter Fertilizer

Ferilome’s New Lawn Starter Fertilizer is the perfect low-cost lawn food for rapid growth and establishing a solid root system. Use it for fertilizing new sod, seeding, or adding sprigs to barren patches.

Apply this product and work it into the first 2-3 inches of soil before planting sod and sowing seed or immediately after to see the best results. Lightly water after application, being careful not to flood your garden and merely dampen the soil.

Reviewer’s comments:

  • Pros: Adding micronutrients makes it an effective fertilizer for greening sod and encouraging grass growth.
  • Cons: The product can cause stains on sidewalks or walls if not swept away immediately.

4. The Andersons, Premium New Lawn Starter Fertilizer

If you forgot to sow seed in summer and don’t want to sit with a barren lawn all winter, The Andersons’ Premium New Lawn Starter Fertilizer has you covered. When using this product, seeding in fall or early spring is best to avoid weed competition and for the ideal soil temperature. Work the starter into the soil 3-5 inches deep before seeding.

The Andersons are reputable in the lawn industry. They provide top-quality gardening advice and products such as their starter lawn food, which contains additions like iron and micronutrients. Their expert knowledge has created a top-quality fertilizer for new sod.

Reviewer’s comments:

  • Pros: Shows full coverage results within two weeks and makes grass green.
  • Cons: Granules are large and can feel awkward to spread.

5. Greenview, Starter Fertilizer

The Starter Fertilizer from Greenview is perfect for establishing new sod and reseeding. It uses a special GreenSmart ingredient (a nitrogen release technology) that feeds roots, helps green grass, and helps the roots retain water. As a result, this product is excellent for areas that experience great heat and drought.

Greenview recommends its application in early fall or spring when soil is still moist and ideal for new seed germination.

Reviewer’s comments:

  • Pros: Shows visible greening within days of application and assists lawn in drought resistance.
  • Cons: Overapplication will lead to burns in the grass.

When to Apply Starter Fertilizer

Apply fertilizer before or after laying sod or seeding. If you apply starter fertilizer first, you must mix it into the soil; this way, the nutrients are readily available for growth and for establishing a strong foundation.

Once you have used a starter fertilizer, you need not apply it again. If you apply a starter fertilizer below the seed or sod, you must wait 6-8 weeks before fertilizing again, as it can cause a chemical imbalance. Any additional fertilizing should be with lawn food for established lawns.

Be sure to check whether your fertilizer is fast or slow, as this will affect how long to wait before applying fertilizer again. Slow-release lawn food takes longer to break down, so a minimum time to wait before fertilizing again is 6-8 weeks. Fast release breaks down quicker and can be reapplied sooner at the soonest of 4 weeks.

For the best results, apply fertilizer in the morning or after the sun has set in the evening and avoid application on windy days. Planting and seeding can occur year-round; however, since establishing new grass requires a high moisture content in the soil, consider seeding and laying sod in early fall and spring months.

Final Thoughts

Choosing lawn food for fertilizing new sod and seeds is a question of what nutrients your soil needs and the desired coverage area. Well-known lawn care brands offer starters with high phosphorus and nitrogen levels as they help establish a strong foundation for roots.

Starter fertilizers provide fast growth and support the grass blade from within. Lawn food for new sod is perfect for establishing strong foundations throughout the year. It works exceptionally well in spring and fall. Applications at these times guarantee beautiful lawns through the harsh winter and summer.

About the author 

Ken Wilson

Long time career in the home services industry from remodeling to patio construction. Currently residing to in SWFL and active contributor to multiple home & garden publications.