Competence in
natural raw materials
from renewable
BIO-PROTAN®Liquid Humus
BIO-PROTAN®Liquid Humus
BIO-PROTAN®Liquid Humus

BIO-PROTAN®Liquid Humus

Product key points

  • Liquid potassium humate suspension with 18% of bioactive humic acids and fulvic acids
  • Soil conditioner and growth stimulant
  • To increase water-holding capacity of the soil
  • Reduces nutrient leaching and increases the effectiveness of fertilizers
  • “Made in Germany” from German Leonardite
  • Product suitable for use in Organic Farming

Humic substances and humic acids

Humic substances origin from the microbial degradation (humification) of dead plant matter, such as lignin. They are very resistant to further biodegradation. Humic substances in soils and sediments can be divided into humic acids, fulvic acids and humin. Humic acid is a main component of humic substances, which are the major organic constituents of soil humus. Humic and fulvic acids (fulvic acids are humic acids of lower molecular weight and higher oxygen content than other humic acids) are commonly used as soil supplements in agriculture. Organic matter soil amendments have been known by farmers to be beneficial to plant growth for longer than recorded history. However, the chemistry and function of the organic matter have been a subject of controversy since humans began postulating about it in the 18th century. Until the time of Liebig, it was supposed that humus was used directly by plants, but, after Liebig had shown that plant growth depends upon inorganic compounds, many soil scientists held the view that organic matter was useful for fertility only as it was broken down with the release of its constituent nutrient elements into inorganic forms. Nowadays, soil scientists hold a more holistic view and at least recognize that humus influences soil fertility through its effect on water-holding capacity of the soil. In addition, since plants show to absorb and translocate the complex organic molecules of systemic insecticides, scientist can no longer discredit the idea that plants may be able to absorb the soluble forms of humus. In fact, this is an essential process for the uptake of otherwise insoluble iron oxides.

An actual study on the effects of Humic acid on plant growth was conducted at Ohio State University in 2006 and said in part “humic acids increased plant growth” and there is a “relatively large responses at low application rates.”1

Product description

BIO-PROTAN®Liquid Humus is a natural and balanced soil conditioner and fertilizer obtained through alkaline extraction from German Leonardite (highly oxidized lignite). The organic material originates from geological processes and biological activity.

BIO-PROTAN®Liquid Humus used alone or mixed with most fertilizers is a permanent humic substance which cannot be easily decomposed by microorganisms of the soil. Liquid Humus is suitable to all agricultural and horticultural plants and unleashes its full and lasting impact especially with sandy and clay soils.

We recommend the regular soil application of BIO-PROTAN®Liquid Humus to improve soil conditioning and soil fertility, stimulate root growth and increase biomass. Use Liquid Humus for fertigation and foliar spray to support the absorption of mineral fertilizers and nutrients naturally present in the soil. Humic Acids are natural chelates able to form chelate complexes and improve the resorption of trace metal fertilizers (Mg, Ca, Fe). The formation of (chelate) complexes is an important aspect of the biological role of humic acids in regulating the bioavailability of metal ions.

BIO-PROTAN®Liquid Humus is free from any chemical components that could be harmful to the soil and crops.

1 Arancon, Norman Q.; Edwards, Clive. A.; Lee, Stephen; Byrne, Robert (2006). "Effects of humic acids from vermicomposts on plant growth" (PDF). European Journal of Soil Biology 42: S65.

Guaranteed analysis (%w/w)

Organic substance 60% DMB*
Organic acids:
Potassium humates 18%
- Humic acids 16%
- Fulvic acids 2%
Organic Nitrogen (N) 1% DMB*
Organic Carbon (C) 35% DMB*
Minerals 5%
Potassium (K2O) 2,5%
Iron (Fe) 0,2%
Water 75%
Particle size < 100 µm
pH Value 9 - 10,5
Density 1,12 kg/L

* ... Dry Matter Basis

Directions for use

We recommend BIO-PROTAN®Liquid Humus for localized soil irrigation and together with regular fertigation.

ml/hl H2O / application during season
MAXIMUM CONCENTRATION 150 ml/100L (0,15% concentration) 10 L/ha application / 50 L/ha total
Every two weeks up to 2 - 5 times
5 – 10 L/ha application / 25-50 L/ha total
once/week up to 3 - 5 times
(tomatoes, peppers, eggplants, cucumbers, zucchini; kiwi, citrus, groves, wine grapes stone fruit)
35-45 L/ha divided into several doses
(5-10 L/ha)
Open field vegetables, cereals, potatoes, beans, peanuts 25-30 L/ha divided into several doses
(5-10 L/ha) during fertilizer application
Ornamental plants and forest nursery, landscaping, turf grass 35-45 L/ha divided into several doses or 5 L/m3 during the preparation of substrates
Seed treatment
(Stimulation of seed germination and root Growth)
5 L/100 Kg seeds

Dilute BIO-PROTAN®Liquid Humus before using it on plants. The recommended application may be varied according to the soil characteristics and local conditions.

Handling and storage

BIO-PROTAN®Liquid Humus is stable when stored under normal undiluted conditions. Intended for immediate use when diluted. The original product in the state in which it is delivered is hazard–free concerning the transmission of pathogens. Close package properly after use. Shake well before use.


Size Units/pallet Pallet dim. [cm] Net weight Gross weight
1.000 L/1.120 kg IBC 120 x 100 x H120 1.120 kg 1.180 kg
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