Powerful Organic Soil Detox & Nutrient Booster for All Growing Conditions
If your soil is tired, depleted, or struggling to retain nutrients, this is your natural fix. Plant Doctor’s Humic Acid 80% Powder is a 99% water-soluble humate made from premium Leonardite, one of the richest known sources of humic acids. It works below the surface to unlock nutrients, detox harmful residues, and restore soil health by feeding beneficial microbes and improving structure. Whether you're growing lush lawns, thriving veggie patches, or managing broadacre farmland, this humic acid powder will rebuild fertility, balance pH, and enhance fertiliser performance, naturally.
SAFE FOR USE NEAR ANIMALS & CHILDREN
Use Humic Acid Powder when organic carbon is low, nutrients are locked up, or you need to improve water retention, especially during high-demand growth stages or when enhancing fertiliser and biological input performance, ideal for those transitioning to organic or regenerative soil programs.
Nutrient Profile:
Humic substances: ~80% (potassium humate base) derived from Leonardite. Contains naturally derived organic carbon compounds and trace minerals. Designed to improve soil function, nutrient availability, and biological activity
Why choose Humic Acid 80% Powder:
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This humate powder is extracted from Leonardite, a natural deposit formed over millions of years, far more concentrated and stable than peat-based sources. Rich in short- and medium-chain humic acids, it acts as a bio-stimulant, soil detoxifier, and chelator.
| Soluble Powder | Foliar: | Mix 1-3kg/1000 Litres water, fortnightly |
| Soil/Fertigation: | 5-10kg/1000 Litres water, apply fortnightly | |
| Salt Problems: | 1-3kg/1000 Litres water, apply fortnightly | |
| Home Garden: | 10-30gm/10 Litres water, weekly | |
| New Plants: | 2gm/Litre water, weekly | |
| Granular - Insoluble | Vegetables: | 50-150kg/1000㎡ |
| Fruit: | 150-200kg/1000㎡ | |
| Cereals: | 75-150kg/1000㎡ | |
| Industrial Crops: | 75-200kg/1000㎡ | |
Not sure how much to apply for your lawn or garden area? Use our Plant Doctor Product Rates Calculator to get the correct rate tailored to your size and conditions.
Keep out of reach of children. May be harmful if swallowed. If eaten seek medical help. ALWAYS TRIAL BEFORE CHANGE. Staining may occur. 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 with iron-based products
Yes, it is 100% water-soluble, but it may require a bit of effort to fully dissolve. We recommend pre-mixing the powder in a small jar or mug with around 100–150ml of water. Stir thoroughly, then pour into your watering can or sprayer. Repeat until fully dissolved.
It improves soil structure, boosts nutrient uptake, and stimulates microbial activity. It’s ideal for enriching tired soils in lawns, gardens, farms, and even hydroponics systems.
Yes. It is derived from natural sources and suitable for organic gardening practices.
Application frequency depends on soil condition, but every 2–4 weeks during active growth is a common guideline.
Yes, humic acid enhances fertiliser efficiency and nutrient uptake. A jar test is always recommended before mixing with other products.
Absolutely. It's suitable for lawns, vegetables, flowers, trees, and even indoor plants.
Humic Acid works in the soil to improve structure and nutrient holding. Fulvic Acid is smaller in molecular size and aids in nutrient delivery within plants.
Yes, if fully dissolved. It can improve nutrient chelation in hydroponics or aquaponics systems but ensure your emitters are compatible.
Store in a cool, dry place out of sunlight. Reseal tightly to prevent clumping from moisture exposure.
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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.
Will definitely be getting more 8 weeks difference been using stimulizer, activ8mate, soil wetter, seaweed secrets and champion fertiliser. Was super fast delivery.
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!
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