Enhance Soil Health & Boost Plant Growth Naturally
Collects Various Pollutants
Improves Soil Quality
Feeds Beneficial Microbes
100% Organic
Humic acid is a powerful, natural way to enrich your soil and support plant growth. It provides essential nutrients, vitamins, and trace elements while improving soil structure and microbial activity. Sourced from Leonardite, one of the richest sources of humic acids, this highly concentrated organic compound has undergone 70 million years of natural humification—far superior to peat, which forms over only a few thousand years.
Key Benefits:
Benefit
Description
Enhances Nutrient Availability
Acts as a chelating agent, making soil nutrients more accessible to plants.
Supports Microbial Life
Encourages beneficial microbes while reducing harmful ones.
Improves Soil Moisture Retention
Helps retain water for healthier root development.
Detoxifies Soil
Reduces the impact of pollutants such as herbicides, pesticides, and heavy metals.
Buffers Soil pH
Helps balance pH levels for optimal plant growth.
Builds & Repairs Soil Structure
Enhances aeration, drainage, and overall soil quality.
Reduces Salt Stress
Binds excess salts to protect plant roots.
When to Use:
When organic carbon levels are low
When soil nutrients are locked up and unavailable
Before planting or during critical growth stages (flowering/fruiting)
Alongside fertilisers to enhance their effectiveness
Application:
Suitable for all plants and soil types
Compatible with most fertilisers, nutrients, pesticides, herbicides, fungicides, and defoliants
Can be mixed with liquid fertilisers, applied pre-planting, side-dressed, or used in irrigation systems
Note: Staining may occur. Always perform a jar test before making changes to your application routine.
Boost your soil’s health with Plant Doctor Humic Acid—a natural powerhouse for better plant growth!
Salt Problems: 1-3kg/1000 Litres water, apply fortnightly
Home Garden: 10-30gm/10 Litres water, weekly
New Plants: 2gm/Litre water, weekly
Vegetables: 50-150kg/1000㎡
Fruit: 150-200kg/1000㎡
Cereals: 75-150kg/1000㎡
Industrial Crops: 75-200kg/1000㎡
Popular Questions
Q. Is the powder 100% soluble?
A. Yes, but it may take a little bit of mixing to dissolve. I suggest pre-mixing it in a small jar or mug first as it takes a little bit to dissolve. Fill the jar up with about 100-150ml of water, then mix, tip into the watering can (or application device), there will be some powder still stuck to the jar, so I add another 100-150ml of water and mix again. Continue doing this until all dissolved.
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Amount of Reviews: 15
Plant Doctor Humic acid (Humate) Powder - Soluble
By: Phoebe on 7 February 2022
this product does very good job on my garden.I use it on fig trees,veg garden,orange trees.It helps keep the roots of plants healthy.I am very happy with this product.
Highly recommend
By: Alexander on 4 December 2020
This is an awesome product, which is great value given the application rates. As always, product was delivered promptly as well. Two thumbs up.
Fantastic product
By: Adam on 23 September 2020
Great product for the lawn, can see great results from applying over a few seasons
Excellent,fair and super-fast
By: Johanne on 23 September 2020
Excellent quality product, fair price (possibly too cheap for the quality), and super-fast delivery even in this current climate.. ill be using again.
Amazing results.
By: Brandon on 25 August 2020
Definietly see the benefits in my lawn from using humic acid
Humic Acid Powder
By: Michael on 2 July 2020
Fantastic results, will definitely be purchasing more down the track. Only need a small amount if applying with a pressure sprayer.
Humic Power
By: robert on 2 August 2019
Using in conjunction with other PDr products. Mixes well after making 3L batches. Soil activity has really improved. Will continue to use in lawn mix.
Deep green /great soil
By: phillip on 18 June 2019
Feeding this to my lawn really helped bring out the deep green colour and you can see it really helps release the available nutrients in the soil ... great product
Great old fashioned service
By: Dan on 7 February 2019
So I only just received this product so I can’t really review it .but the service I received was fantastic and the guys here really do care about every customer ,I only ordered 1kg of the product but they treated me the same as a customer that spent a $1000 . Just wanted to let you guys know ,keep up the great work
The Black Stallion
By: Michael on 2 January 2019
This stuff is great. As I use a backpack sprayer to apply I mix amount I need in a bucket with a few liters of water, mix with a stick and then while preparing my other plantdoc products it dissolves completely. This has brought great balance and health to the soil. Seen an increase in worms which is great. Grass seems to be less brown and less sunburn spots in the hot days.
Humic powder
By: mark on 5 November 2018
Great product easy to use,been applied with your liquid iron and stimulizer have noticed a big change in the lawn
Mix it up
By: Mathew on 4 November 2018
I mix with luke-warm water to make it soluble and add to other plant doctor products, my root growth has been fantastic since using this product.
Great product
By: Brett on 31 October 2018
have been using this for a couple of months now & you can really see the difference! Great value for money as a small amount goes a long way!!
Humic acid
By: Corbin on 20 October 2018
Been using this on my lawn for a few months and it has helped the soil microbiology. I have a premdominate sand based and now I get small mushrooms which indicates excellent health. Mixing with a stirer/while mixing is key as it can clump otherwise
Great product
By: Ashley on 11 October 2018
Been using this product for over 3 months on lawn and vegetables. So far results seem great.
Only negative would be that it is difficult to mix up. Not that soluble.
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Australian Owned
Australian family owned and operated. Online sales since 2009.
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Flat-rate shipping from $9.95* Fast and affordable! *For items 1 kilo or less, shipped within Australia. $14.95 for above 1kg. Excludes some regional areas.
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Customer Reviews
5
First time owning lawn. Gave the team at plant doctor a ring and they supplied me with a wealth of information. Products turned up quickly.
Billy Green
5
Will definitely be getting more 8 weeks difference been using stimulizer, activ8mate, soil wetter, seaweed secrets and champion fertiliser. Was super fast delivery.
Michael Preddy
5
Only have great things to say about Plant Doctor. Organic products and a competitive price, fast shipping and easy to contact with questions. Have had great results with the special mix for lawns, and my plants (indoor and outdoor) love the seaweed secrets. I am excited to test out some of the animal products soon!