Quantum H® Liquid Humic Acid Lawn & Garden Soil Conditioner - 1L

Leonardite-sourced. Improves soil structure and uptake.

Quantum H is a premium humic acid soil conditioner that improves soil structure, boosts microbial activity and enhances nutrient availability. It helps unlock locked-up nutrients, supports root growth & improves soil health for all lawns, plants & crops.
Humic + Fulvic Soil Concentrate Boosts Soil Function & Nutrient Uptake Fixes Tired, Locked-Up Soils
LawnsGardensFarms
$19.95
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Description

Premium Liquid Humic Acid Soil Conditioner for Healthier, Fertile Soil

Quantum H isn’t just another soil additive, it’s a powerful organic soil conditioner made to repair tired, nutrient-starved, or contaminated soils and turn them into rich, living ecosystems that support healthy plant growth. Formulated from premium Leonardite ore, Quantum H delivers short-chain humic and fulvic acids that work fast to unlock nutrients, detoxify chemicals, and feed soil microbes, restoring balance and fertility from the ground up.

Use Quantum H when your soil shows signs of organic carbon deficiency, poor nutrient uptake, or symptoms of “nutrient lock-up.” It’s especially valuable for rehabilitating soils affected by chemical residues such as herbicides, pesticides, or heavy metals. In hydrophobic or compacted soils, it helps improve moisture infiltration and microbial activity. It’s also an essential input for growers transitioning to regenerative or organic farming systems, where building long-term soil health and fertility is key.

Good for soil. Have noticed a huge improvement all around in my garden after applying this, especially on sections that were struggling before.
— Dario
Why choose Quantum H:
  • Rebuilds damaged or depleted soils
  • Boosts water retention & soil structure
  • Feeds beneficial microbes and unlocks nutrients
  • Binds harmful residues (salts, pesticides, herbicides, heavy metals)
  • Improves root development and nutrient uptake
  • Compatible with most fertilisers and crop inputs
  • Organic, clean, and easy to apply
Nutrient Profile:
  • Humic substances: liquid potassium humate concentrate
  • Contains organic carbon complexes and naturally occurring trace minerals
  • Designed to improve soil chemistry, nutrient availability, and biological efficiency

Quantum H's low sludge formulation makes it easy to handle and ideal for various application methods. Rich in bioavailable organic carbon, it supports soil biology and long-term fertility. Quantum H is compatible with most crop inputs including fertilisers, pesticides, fungicides, and biologicals, except iron-based products, which should be applied separately. It can be used year-round and is particularly effective when applied during seedling, transplanting, fertigation, or pre-planting to activate soils and boost early plant development. 

 

If your soil is compacted, tired, chemically stressed or nutrient-poor, Quantum H is your reset button. With every drop, you’re restoring balance, feeding life back into the ground, and giving your plants the foundation they need to thrive.

(29800)

Features

Quantum-H functions as a soil performance and nutrient efficiency catalyst, not a nutrient source. Quantum H has the following benefits:

Chelation & Nutrient Release

Breaks bonds that lock nutrients in the soil, making them available to plants

Water Retention & Soil Structure

Improves porosity and reduces runoff, helping roots access more water

Microbial Activation

Feeds soil microbes that break down organic matter and cycle nutrients

Soil Detoxification

Binds and neutralises heavy metals, herbicide residues, and excess salts

Carbon Source

Supplies organic carbon critical for soil biology and humus formation

Root Support

Encourages deeper, more fibrous root growth for better drought resilience

In summary: 

  • Improves soil cation exchange capacity (CEC)
  • Enhances nutrient retention in the root zone
  • Chelates and unlocks tied-up minerals in soil
  • Stimulates microbial population activity
  • Improves soil structure, aggregation, and moisture dynamics
  • Increases fertiliser efficiency across all inputs

 

How it Works

The Science Behind Quantum H:

Quantum H is more than a soil conditioner, it's a soil activator that changes the way your soil functions at a biological and chemical level. Powered by short-chain humic and fulvic acids extracted from high-grade Leonardite ore, it enhances the soil’s cation exchange capacity (CEC), buffers pH, stimulates microbial life, and unlocks bound nutrients in the soil matrix. Humic substances are the most active component of organic matter in soil, formed through the natural breakdown of ancient plant and animal materials. Within this group are three key compounds:

  • Humic acids – large, complex molecules that improve soil structure and nutrient retention
  • Fulvic acids – smaller, water-soluble molecules that chelate nutrients and facilitate their rapid absorption by plant roots
  • Humin – the least active, most stable fraction of organic matter

Quantum H contains a high concentration of short-chain humic and fulvic acids, which are more biologically active and effective than longer-chain forms. This makes it a fast-acting, high-performance input.

Application

Application Type Details
Home 1ml per 1sqm
100ml per 100sqm
Apply fortnightly or as required.
Broadacre 6 - 10 Litres per hectare in enough water to provide thorough coverage or 1000 litres of water, reapplying 2-6 times during the growing season. It may be water run, side dressed, mixed with soil applied with liquid nutrients or sprayed directly on the soil.
Added with nutrients Add 2-4 litres of Quantum H per Hectare mixed with the liquid nutrients. Add to a partially filled tank. Include with every application.
Sprinkler or Drip Irrigation Smaller amounts may be applied in every irrigation instead of only one application. Not corrosive to pipes or nozzles and will not plug them.
Transplanting or Cutting Mix 4 litres of Quantum H per 750 litres of solution.
Mix well before use – Dilute in at least 1:20 in water.
Agricultural Specific Recommendations Vegetables: 600ml per 100L water up to 3.5L/ha equivalent. Apply every 2 weeks or as required.

Orchards & Vineyards: 600ml per 100L water up to 5L/ha equivalent. Apply every 4 weeks or as required.

Ornamentals & Turf: 600ml per 100L water up to 3.5L/ha equivalent. Apply every 4 weeks or as required.

Pasture: 1 – 3L/ha in 60 – 100L water. Apply as required.

Broadacre Crops: 0.6 – 2L/ha in 60 – 100L water, depending on canopy closure. Apply as required.

Spot-Spraying: 35ml per 10L water. Apply as required.
Fertigation Vegetables: 6 – 10L/ha. Apply every 2 weeks or as required.

Orchards, Vineyards, Ornamentals & Turf: 6 - 10L/ha. Apply every 4 weeks or as required.

 

Safety

Safety Guidelines

Keep out of reach of children. May be harmful if swallowed. If eaten seek medical help. ALWAYS TRIAL BEFORE CHANGE. Before a new rate, product or application method is used, a small trial is recommended. Warranty of this material, either expressed or implied is limited to a guarantee of the composition as shown on this label in as much as uses are beyond the seller’s control. For the same reason, the seller is not liable for any injury to any living thing, crops, soils, or materials which may result from the use or storage of this material. As this is largely a mineral based fertiliser made from natural resources, the analysis may change slightly.

NOTE: Not compatible to be mixed with iron-based products. Apply separately.

FAQ

What is Quantum H used for?

Quantum H is a premium humic acid solution designed to improve soil structure, increase nutrient uptake, enhance microbial activity, and support plant and lawn health. It’s ideal for all soil types and can be used on lawns, gardens, trees, and crops.

How often should I apply Quantum H?

Quantum H can be applied every 2–4 weeks depending on your lawn or garden's condition. Refer to the application rate guide for specific use instructions.

What is the application rate for Quantum H?

Refer to the application rate table on the product label or website for specific rates tailored to lawns, gardens, or agricultural use.

Can I use Quantum H on all lawn types?

Yes, Quantum H is safe for all Australian grass varieties including couch, buffalo, kikuyu, and zoysia.

Can I mix Quantum H with fertilisers?

Yes. Humic acid enhances the performance of most fertilisers by increasing nutrient availability and reducing losses through leaching or lockup.

Is Quantum H compatible with other Plant Doctor products?

Absolutely. It pairs well with Seaweed Secrets, Stimulizer, and Activ8EXTRA as part of a complete soil health strategy.

Is Quantum H organic?

Quantum H is made from natural leonardite sources and contains humic and fulvic acids. It is not certified organic but is non-toxic and environmentally friendly.

How does Quantum H improve soil health?

It helps restructure compacted soil, boosts microbial activity, improves moisture retention, and keeps nutrients available to plants longer.

Can I use Quantum H in sandy or clay soil?

Yes. In sandy soils, it helps hold moisture and nutrients. In clay soils, it improves drainage and reduces compaction.

Is Quantum H safe for pets and children?

Yes. Once the product has dried after application, treated areas are safe for kids and pets to return to.

Can Quantum H be used in hydroponics?

It can be used in small amounts in hydroponics to support nutrient uptake and microbial life. Test on a small scale first.

Reviews

5.0 / 5

customer reviews

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Awesome product!

I’ve been using Quantum H on my rose beds for several weeks now. The soil is noticeably healthier, and so are the plants. I highly recommend this if your soil is a bit iffy and needs a lift.

Brilliant

I have been using Quantum H on my Santa Anna lawn now for years in conjunction with other PD products and the results have been consistently brilliant. I have found that maintaining soil health is critical component in lawn care, and Quantum H is definitely a part of a “system” to use to achieve results.

Awesome products

Can’t believe how good my lawn is looking 12 months into using plant dr products. Currently using 5 products and my lawn is mint. Every time I look at it I get tingles in the loins region!

Quantum H

Recently we have had warmer weather combined with some high winds and QuantumH has really helped get the most nutrients out of my soil whilst helping retain some moisture in these tougher times! Couldn’t be happier with the results from this product!!

Good stuff

Been using this one in combination with a few other PlantDoctor products to help repair and bring life back to a struggling and somewhat neglected lawn. Couldn't be happier how fast it's bounced back and looking solid and healthy for summer!!

Fantastic product

I ordered this product after recommendations from various YouTubers who achieved amazing results from using this. I am really excited to try this on before spring kicks in this year. Delivery was super quick. Thanks guys ..

Quantum H

I have used this product in combination with 5 other Plant Doctor products for the past four years and my Sir Walter lawns are pretty spectacular. The service and delivery are both prompt and efficient.

Much needed soil revitalizer

Quantum H helped revitalize my otherwise dead clay soil, can't recommend enough!

Good for the soil

Have noticed a huge improvement all round in my garden after applying this specially on sections that were struggling before.

Awesome Product

I love every product from this company. I use them both for home and for my business

Feed the Microbes

We all know that microbes are the best for an organic garden so I use this as food for them and help improve the soil

LUSH AND GREEN

Love this product, made my new lawn from light green to a bright vibrant green in only two applications! Highly recommend. Purchased as part of the Lawn Lovers Pro Pack.

Great team and product

I bought the 10L as it represents great value. I am super impressed by the results, i have combined with seaweed secrets and stimulizer. I am 100% placing more orders and recommending to friends and family.

Another great product

Great way of feeding microbes and creating nutrient dense food

Healthy plants

I had a few issues with a couple of plants that seemed to be struggling, including water logged. After applying this product, within a month I noticed new health fresh growth that has absolutely turned my garden around for the better

Quantum h

Great product

Top Quality

I've been using Plant Doctor liquid fertilizers for some time now, and I can't fault them. They are of a high quality, and make my lawn look exceptional. I use Quantum H regularly on my lawn, and you can see the difference!

Quantum H

Fantastic product. I love it. Just adds that extra something to my fertiliser mix

HUMIC

I use Qantum H as apart of the Lawn Lovers bundle. Humic acid helps keep your soil healthy!

Great Product

Great product at an even better price!

top notch

Fantastic product to help in the conditioning of my sandy soil profile. value for money!

Little goes a long way

This product does wonders for the lawn, you can really see the difference after a couple of applications

Great stuff

First time using a product like this. Have to say combined with everything else my lawn is thriving! great stuff

Keen to use!

The post was quick. Clean. Well packed. Thank you

Great Product

Excellent results on my Kik in SEQ, very quick postage and great communication, highly recommend

Grass looking better than ever.

I watch a lot of lawn videos and a lot of them have been using this. I thought I would give it a go as I have very sandy soil that really is lacking in goodness. After a week I can already see the difference! Why did I wait so long. Do yourself a favour, try it. You won't regret it. My eyes are opening to grass greatness!!!!

5 star praise

First time taking on a lawn reno and with help and guidance from the plant doctor my lawn is looking amazing. This stuff is so easy to use with simple application instructions right there on the bottle you will get results in no time at the fraction of the price

Humic acid

Again another quality product at a good price..

Humic acid

Again another quality product at a good price..

Brilliant product for soil amendment

I had issues with consistency in soil qaulity but after applying Qauntum H lawn looked great!

Really works

Great product, improves soil and makes lawn (santa ana) look green and healthy when used with other plant doctor products

Amazing Green Zoysia

I use the Plant Doctor Quantum on both my Empire and Augusta Zoysia in conjunction Natures Soil Wetter, Liquid Iron, Stimulizer, Seaweed Secrets and Activ8Mate and they bring a depth of healthy colour to my lawn that I have not seen with any other combination of products that I've tried

Quality

Quality product! Have used on both my lawn and plants and can really notice the difference this makes! Plants and lawn are a lot healthier!

Great product!

Gave the lawn the suggested amount and it's come up thick and green within a month, even in areas where it struggled to grow before. Will be buying more!

Great all-rounder!

Great all-rounder!

Loving this !!

Works a treat. Lawn has never looked better. Easier to use when compared to using the powered humic acid. Free shipping with orders over $59 is the icing on the cake.

Awesome Product

Does everything as described.

Versatile foliar spray

I needed to buy a bigger bottle this time as I ran out. Quantum H and seaweed secrets are so versatile I spray them on everything: the lawn, fruit trees, strawberries. And I get great results.

Quick to arrive

Ordered some Quantam H (20L) in a bundle. Arrived the same week. Highly recommended

Lush!

Ran out of this product for a few weeks and wow did i notice a difference now i have stocked up again even just 2 applications down and the lawn is back to stunning results (maintaining soil moisture for longer, density and all round health of the plant) highly recommend this product.

Great product

Used with other plant doctor products to make a real difference to the garden

Great

Been applying this with my Ben Sims mix with great results.

Great product

Great addition to my lawn arsenal! Great price too!

Rich soil

Another great soil conditioning product when mixed with seaweed secrets and Stimulizer, has helped fix many issues I had with a new lawn area.

Quantum H

Combined this with the other Plant Doctor products and have made a huge improvement on my lawn. Awesome product

Quantum H

Thank you Adam for the quick service and delivery. You have a new client here, very happy !

Awesome product

Heard a lot about Humic acid benefits. So got this to try. Looking forward to see results.

Must have product!

QH is a must have product in your garden shed. I make it a point to mix this liquid solution with Seaweed Secret and Stimulizer to get super results and the magic blend has never failed me thus far. Plus, its an organic product that I use on my little vegetable patch too.

Lawn repair

I'm using Quantum H with an oversow to repair dog urine damage to the lawn. The germination was fast and I'm already seeing some improvement with the damaged patches reviving the existing grass plants.

Liquid Gold !

I have only applied this several times and I can notice the improvement to the soil in my vege garden already.

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Customer reviews

What customers are saying

5.0 from 0 verified reviews

Awesome product!

I’ve been using Quantum H on my rose beds for several weeks now. The soil is noticeably healthier, and so are the plants. I highly recommend this if your soil is a bit iffy and needs a lift.

KerryS. Verified review

Brilliant

I have been using Quantum H on my Santa Anna lawn now for years in conjunction with other PD products and the results have been consistently brilliant. I have found that maintaining soil health is critical component in lawn care, and Quantum H is definitely a part of a “system” to use to achieve results.

NoelL. Verified review

Awesome products

Can’t believe how good my lawn is looking 12 months into using plant dr products. Currently using 5 products and my lawn is mint. Every time I look at it I get tingles in the loins region!

jade m. Verified review

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Brilliant

I have been using Quantum H on my Santa Anna lawn now for years in conjunction with other PD products and the results have been consistently brilliant. I have found that maintaining soil health is critical component in lawn care, and Quantum H is definitely a part of a “system” to use to achieve results.

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