An organic mineral very rich in humic acids, formed by the decomposition of plant matter over millions of years; it's the usual source of humic amendments.

How long does it take to see the effect of humic acids?

Nutrient uptake improves within a few weeks; soil structure improves gradually with continued applications.

Humic Acids and Organic Amendments: How to Restore Tired Soil

Q: Liquid or solid humic?

Liquid is more convenient to handle; the soluble solid concentrates more content per kilo and is more cost-effective on large areas.

Quick answer: humic and fulvic acids are the most active fraction of soil organic matter. They improve soil structure, increase its capacity to hold water and nutrients (cation exchange capacity), and stimulate microbial life. They're recommended for tired soils, soils low in organic matter, or heavily mineralized soils, and are mainly applied via fertigation.

Humic vs. fulvic acids: what's the difference?

Humic acids: large molecules that act mainly on the soil: they improve its structure and retain water and nutrients.
Fulvic acids: smaller, more soluble molecules that help transport nutrients into the plant.

A good amendment combines both.

Signs your soil needs an amendment

The soil compacts or crusts over, and water pools or runs off.
Fertilizers "don't seem to work": nutrients get washed away or locked up.
Years of monoculture or purely mineral fertilization.
Poorly developed roots, or crops that respond worse each season.

Which amendment to choose

Product	Composition	Recommended for	Recommended dose
Humus Puro	Liquid from American leonardite: 15% humic extract (12% humic, 3% fulvic), 3% K₂O	Tired, heavily mineralized soils	Fertigation 8-10 L/ha
Humus Sólido	100% soluble solid concentrate: 70% humic extract (55% humic, 15% fulvic), 6% K₂O	Maximum concentration for fruit trees, citrus and vegetables	Fertigation 15-25 kg/ha
Vitalia Suelo Plus	Plant extracts with organic acids; 40% organic matter	General improvement of soil structure and nutrient uptake; also for turf and ornamentals	10-20 L/ha
Vitalia Suelo Premium	Plant extracts with lignosulfonates that bind Ca, N and K	Activating microbial life; very good results in fast-cycle crops (lettuce, spinach, carrot)	Fertigation, spraying or drip line 10-20 L/ha
Raíz Libre	Formulation from the professional range	Releasing nutrients locked up in calcareous or compacted soils	Ask our team
Raizan	100% hydrolyzed plant extracts, 7% K₂O, 2% amino acids	Boosting biological activity in the root zone	Fertigation 2 L/ha

If your soil or water is also saline, combine the amendment with a sodium corrector such as Equilibrio.

How to apply a humic amendment

Before or at the start of the crop cycle, to prepare the soil.
Split into several applications throughout the cycle, rather than a single dose.
Alongside your fertilizers: humic substances improve their uptake and reduce losses from leaching.

Frequently asked questions

What is leonardite?

It's an organic mineral very rich in humic acids, formed from the decomposition of plant matter over millions of years. It's the most common source of high-quality humic amendments.

Liquid or solid humic?

Liquid is more convenient for day-to-day handling; the soluble solid concentrates far more content per kilo and is more cost-effective on large areas.

How long does it take to see the effect?

The improvement in nutrient uptake is noticeable within a few weeks; the improvement in soil structure is gradual and builds up with continued applications season after season.

Want to analyze what your soil needs? Ask our technical team. Also see: fertilization plan by crop stage.