10 Best Humic Acid Fertilizer of 2025

Tested and Reviewed: Top 10 Humic Acid Fertilizer deals with expert ratings from 8.1 to a perfect 10

March 2026 Edition

Editor's Choice

9.7

GS Plant Foods

GS Plant Foods Humic Acid Soil Amendment – Leonardite-Derived Liquid Concentrate for Improved Soil Structure & Nutrient Availability – OMRI Listed for Organic Use – 32 Oz

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Editor's bottom line:

“This humic acid fertilizer is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

IMPROVES SOIL STRUCTURE & NUTRIENT AVAILABILITY- GS Plant Foods Humic Acid Soil Amendment supports healthy soil by enhancing cation exchange capacity and helping the root zone access existing nutrients in the soil more efficiently. Derived from high-quality Leonardite.
OMRI LISTED FOR ORGANIC USE- This product is OMRI Listed under the name GS Plant Foods Organic Liquid Humic Acid, making it suitable for use in certified organic growing programs and regenerative soil practices.
DERIVED FROM PURE LEONARDITE- Our liquid humic acid is sourced from premium Leonardite deposits, providing a rich supply of naturally occurring organic matter that contributes to long-term soil health and conditioning.
SUPPORTS A HEALTHIER ROOT ZONE- Humic substances help create a more balanced soil environment by improving nutrient exchange, buffering soil conditions, and supporting strong root-zone developmentwithout synthetic additives or harsh ingredients.
COMPATIBLE WITH MOST FERTILIZER & SOIL PROGRAMS Use with your existing fertilization schedule. Works well for gardens, houseplants, lawns, trees, greenhouse crops, vegetables, and landscape plants. Avoid mixing with low-pH or high-calcium formulations.

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9.5

GS Plant Foods

GS Plant Foods Humic Acid Soil Amendment – Leonardite-Derived Liquid Concentrate for Improved Soil Structure & Nutrient Availability – OMRI Listed for Organic Use – 1 Gallon

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Main Highlights

IMPROVES SOIL STRUCTURE & NUTRIENT AVAILABILITY- GS Plant Foods Humic Acid Soil Amendment supports healthy soil by enhancing cation exchange capacity and helping the root zone access existing nutrients in the soil more efficiently. Derived from high-quality Leonardite.
OMRI LISTED FOR ORGANIC USE- This product is OMRI Listed under the name GS Plant Foods Organic Liquid Humic Acid, making it suitable for use in certified organic growing programs and regenerative soil practices.
DERIVED FROM PURE LEONARDITE- Our liquid humic acid is sourced from premium Leonardite deposits, providing a rich supply of naturally occurring organic matter that contributes to long-term soil health and conditioning.
SUPPORTS A HEALTHIER ROOT ZONE- Humic substances help create a more balanced soil environment by improving nutrient exchange, buffering soil conditions, and supporting strong root-zone developmentwithout synthetic additives or harsh ingredients.
COMPATIBLE WITH MOST FERTILIZER & SOIL PROGRAMS Use with your existing fertilization schedule. Works well for gardens, houseplants, lawns, trees, greenhouse crops, vegetables, and landscape plants. Avoid mixing with low-pH or high-calcium formulations.

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9.5

PowerGrow Systems

Humic Acids - Humic Acid Fertilizer & Conditioner (HUMIC Acid 5 LB Bag)

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Main Highlights

Humic Acids increase plant nutrient uptake
Humic Acids increase soil microbial activity
Humic Acids increase soil health and help seed germination
Humic Acids increase water retention and oxgen in soil
Premium Humic Acids screened to the perfect size for gardens

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9.2

Down To Earth All Natural Fertilizers

Down To Earth All Natural Fertilizers Organic Granular Humic Acids - Soil Amendment Adds Carbon, Increases Nutrient Uptake, 5 lb

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Main Highlights

Down to Earth Granular Humic Acids is a five pound box of all natural fertilizer and is listed by the Organic Materials Review Institute (OMRI) for use in organic production
A highly concentrated source of humic acids ideal for use on fields, turf, vegetable gardens and may potentially increase a plant's ability to take up micronutrients from the soil
Carefully mined from one of the worlds richest deposits and is derived from the ancient remains of decomposed organic plant materials
Humic acids enhance nutrient uptake and stimulate soil microbial life and is a great way to introduce long-term, stable organic matter to your garden
Naturally occurring, unaltered oxidized lignite containing 50% total humic acids, crushed, screened and graded to a particle size of 1-3mm

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9.0

The Andersons

The Andersons Humic DG Organic Soil Amendment - Covers up to 40,000 sq ft (40 lb)

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Main Highlights

Carbon soil amendment increases soil carbon and soil organic matter
Highly concentrated 70% humic content (A&L method). Feeds beneficial soil microbes by providing a key food source, carbon. Chelates nutrients to increase nutrient and fertilizer efficiency; increases nutrient absorption
Improves seed germination, root mass, root vigor and overall root and plant health. Environmentally friendly, OMRI listed
User friendly; can be blended with fertilizers, alongside any fertilizer program or used alone. Highest quality of humate source
Safe for all turf and soil types. Not for sale in SD

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8.8

The Andersons

The Andersons HumiChar Organic Soil Amendment with Humic Acid and Biochar Covers 12,000 sq ft (12 lb)

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Main Highlights

Improves soil health, lawn health, plant health, and reduce the use of fertilizers
Easy to apply spherical, uniform, low dust formulation. Dispersible Granule, or "DG" Technology is The Andersons' patented nutrient delivery system. With DG Technology, particles are more rapidly and efficiently broken down
Environmentally friendly, OMRI listed. User friendly; can be blended with fertilizers, alongside any fertilizer program or used alone
HumiChar is an organic, carbon-based soil amendment. Contains 30% high-quality humic acid and 43% granulated biochar
Provides the benefit of quickly-available humic acid and the long-term soil building qualities of the biochar that lasts for decades. Not for sale in CA or OR

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8.6

Monterey

Monterey Humic Acid 32oz

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Main Highlights

May Be Used As A Transplant Root Dip, Foliar Spray Or In The Soil
Manufactured In United States
Color: White
Size: 32 oz

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8.3

Farmer's Secret

Farmer’s Secret Soil Revitalizer (32oz) - Organic (OMRI Listed) Beneficial Dirt Booster - Activated Humic Acid - Liquid Compost Soil Amendment

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Main Highlights

Feed the soil not the plants - stimulate microbial activity in your soil and boost probability of success with all types of plants like composting but faster
For best results, apply monthly throughout the growing season
No synthetic chemicals - main ingredient in this product is activated humics derived from organic sources (OMRI certified organic)
Concentrated formula - simply dilute at a ratio of 1 oz to 1 gallon and spray/pour on your soil
Farmers Secret products are made with pride in Kentucky and puts the know-how of award-winning farmers into your hands. Get in on the Secret!

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8.1

Bloom City

Bloom City Organic Liquid Humic Soil Health Formula, Great for Houseplants, Gardens and Lawns, Quart (32 oz) Concentrated Makes 30+ Gallons

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Main Highlights

Made for Lawn Soil Health Formulated to support healthier soil conditions for residential and commercial lawns.
Supports Nutrient Uptake & Root Strength Helps improve nutrient availability and supports deeper, stronger root systems.
Enhances Soil Structure & Performance Aids in improving soil efficiency for better water and nutrient retention.
Designed for Regular Lawn Care Programs Works well alongside standard lawn feeding and maintenance routines.
Made in USA

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8.1

Simple Lawn Solutions

Organic Super Seaweed Humic Acid Blend- Liquid Sea Kelp for Grass and Plants - Soil Hume - Simple Grow Solutions- Natural Lawn & Garden Concentrate- Use with Fertilizer Program (32 Ounce)

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Main Highlights

Blended with 4% Seaweed: Liquid Sea Kelp Concentrate blended with Ascophyllum Nodosum Seaweed harvested in the Icy North Atlantic
Blended with 4.5% Humic Acid: Soil Hume is a Highly Concentrated form of Liquefied Carbon Derived from the Highest Quality Humate Source, Leonardite. Leonardite is Considered by many to be the Highest Quality form of Humic Acid
Versatile Formula for Lawn and Garden: Soil Hume Can help increase the Transfer of Nutrients and Help your Lawn, Garden and Plants Uptake Nutrients more Efficiently
Use Alongside Lawn Food Fertilizer Program. Can be used on all grass types including Bermuda, St. Augustine, Zoysia, Buffalo, Centipede, Florida Palmetto, Bahia, Fescue, Ryegrass & Kentucky Bluegrass
Application Rates for Garden: Use on Indoor Plants, Flowers, Roses, Tomato Plants, Vegetables, Fruit, Citrus, Garden Landscape, Hardy trees, Seeding, Over seeding and New sod. Use Alongside Plant Food Fertilizer Program
Easy to Use, Application Rates for Lawn and Garden: Soil Hume can be Applied using a Hose-end Sprayer, Backpack Sprayer, Spray Tank or Pump-up Sprayer or Watering Can
32 ounce, Quart Sized Bottle: Soil Hume is a Quality Soil solution Used Professionally on Commercial Agricultural, Athletic Turf, and Golf Courses
Made and Manufactured in the United States: Manufactured by a Family Business and Used by Farmers and Professionals all over the world for the past 25 years

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Our Best Overall Choice

Best Choice

9.7

GS Plant Foods

GS Plant Foods Humic Acid Soil Amendment – Leonardite-Derived Liquid Concentrate for Improved Soil Structure & Nutrient Availability – OMRI Listed for Organic Use – 32 Oz

Free Shipping

Editor's bottom line:

“This is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

IMPROVES SOIL STRUCTURE & NUTRIENT AVAILABILITY- GS Plant Foods Humic Acid Soil Amendment supports healthy soil by enhancing cation exchange capacity and helping the root zone access existing nutrients in the soil more efficiently. Derived from high-quality Leonardite.
OMRI LISTED FOR ORGANIC USE- This product is OMRI Listed under the name GS Plant Foods Organic Liquid Humic Acid, making it suitable for use in certified organic growing programs and regenerative soil practices.
DERIVED FROM PURE LEONARDITE- Our liquid humic acid is sourced from premium Leonardite deposits, providing a rich supply of naturally occurring organic matter that contributes to long-term soil health and conditioning.
SUPPORTS A HEALTHIER ROOT ZONE- Humic substances help create a more balanced soil environment by improving nutrient exchange, buffering soil conditions, and supporting strong root-zone developmentwithout synthetic additives or harsh ingredients.
COMPATIBLE WITH MOST FERTILIZER & SOIL PROGRAMS Use with your existing fertilization schedule. Works well for gardens, houseplants, lawns, trees, greenhouse crops, vegetables, and landscape plants. Avoid mixing with low-pH or high-calcium formulations.

Show Price

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