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Lawn Booster: Extreme Growth Booster (2.5 Gallon)

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Start your lawn off right with Growth Booster, a high-phosphorus fertilizer!

Growth Booster lawn fertilizer contains the essential macronutrients to help get your new lawn established into a thicker, fuller, envy-worthy lawn! This starter fertilizer is great for seeding and establishing brand-new sod, as its star ingredient is Phosphorus, which is essential for strong plants and roots. Use this liquid lawn fertilizer with humic acid to establish a new lawn or maintain your current lawn.

Growth Booster is a phosphorus fertilizer energized with Humic Acid. Our decades of research have resulted in lawn fertilizers that are expertly manufactured with our proprietary manufacturing method, unlike any other product on the market. Our Humic Acid is derived from what is considered to be the highest quality humate source available, Leonardite. Our humic acid is obtained via a proprietary extraction method versus made from soluble powder making it a very pure and active form.

Who Should Use This Product? Simple Lawn Solutions' Growth Booster is best to be used...

  • As a seed fertilizer when establishing your lawn with seed
  • If your lawn is deficient in Nitrogen or Phosphorus
  • To improve micronutrient uptake

Whether you are looking to maintain your current lawn, correct nutrient deficiencies, or you are starting your lawn completely from scratch, our customer care team and products have you covered! Contact our team for a custom lawn plan tailored to your lawn’s needs! 

Nitrogen 6% Nitrogen is the mineral element used in the greatest quantity by turf. Nitrogen is a component of many of the biochemical constituents of plants, including chlorophyll, amino acids, proteins, and enzymes. The addition of Nitrogen encourages ideal conditions for a dense, attractive lawn.

Phosphorus 18% The proper phosphorus level in your grass is essential for root and early plant development. Its primary role is in the storage and transfer of energy. Without sufficient P, normal growth and development cannot occur. Phosphorus effects on turf are usually more subtle and, while not as readily visible, are still very important.

  • Phosphorus: Excellent for Establishing New sod or seed
  • Nitrogen: Encourages a thicker, greener lawn
  • Aids Nutrient Uptake: Promotes the transfer of nutrients
  • Treats Nitrogen & Phosphorus nutrient deficiencies
  • Covers 32,000 square feet
  • Can be used on all grass types
  • Unique & proprietary formula
  • High-quality, feed-grade ingredients
  • Ready-To-Use sprayer application
  • Proudly made in the USA

For best results, water the lawn for 20 minutes within 24 hours of application. Water is essential for maintaining your lawn, and your lawn should receive 1-2 inches of water per week. Fertilizer will not treat a lawn suffering from disease, pests, weed infestations, or drought, and these conditions should be treated separately.

This fertilizer contains Phosphorus and may not be used for lawn maintenance on turf in Maryland, Michigan, New Jersey, New York, and Virginia except when 1) Providing nutrients to specific soils and target vegetation as determined to be necessary in accordance with a soil test that was conducted by a laboratory* performed no more than 3 years before the application. 2) Establishing vegetation for the first time, such as after land disturbance, provided the application is conducted in accordance with the recommended application rates established by the state. 3) Re-establishing or repairing the turf area. *In Maryland, the soil testing laboratory must be identified under Section 8-803.7 of the Agriculture Article, Annotated Code of Maryland.

Notice: We are temporarily unable to fulfill our products in the following states:

  • Alaska
  • Hawaii
  • Puerto Rico
6-18-0 Growth Booster (2.5 Gallon) Lawn Booster by Simple Lawn Solutions Growth Booster applied with ortho house-end sprayer 6-18-0 Growth Booster applied with [ump sprayer to green lawn Growth Booster Nitrogen, Phosphorus, and Humic Acid Lawn Fertilizer 6-18-0 Growth Booster Benefits, Nitrogen encourages greening and growth, Phosphorus essential for root development, Humic acid promotes micronutrient uptake, great for establishing lawns, and treats nitrogen and phosphorus deficiencies.

Why Simple Lawn Solutions

Made in the USA

All of our products are manufactured in the United States.

Top-notch Service

We offer lawn plans and product recommendations upon request.

Highly Rated

Our products are loved by thousands of customers and their lawns.

Satisfaction Guaranteed

We are so confident in our products, that we offer a 100% satisfaction guarantee.


The journey to my beautiful lawn was not an easy one. At first, I had no idea what I was doing and I was getting mediocre results. I found websites like Simple Lawn Solutions to help me on my journey and you can see the results in the photo. Hope you enjoy.

John F.

Cool Season Grass. The lawn was previously not loved. Just moved in a few months ago and trying to turn the lawn around into something beautiful. Simple Lawn Solutions has been a part of that process.

Joseph B.

The lawn was mostly weeds. We took a soil test, killed the weeds, spike aerated, fixed the soil, and seeded. The lawn was good but SLS put it over the top.

Richard K.

Tall fescue with some mix of Kentucky Blue and Perennial Rye. This picture was taken about a week after using Simple Lawn Solutions Energizer!

Randy B.