humic acid cannabis

The Benefits Of Humic And Fulvic Acids For Growing Cannabis

Increasingly, more cannabis farmers are taking advantage of the benefits of humic and fulvic acids. These acids ensure healthy roots and better nutrient uptake to support happier plants with larger yield potential. Learn why you should incorporate humic and fulvic acids into your next grow.

Humic and fulvic acids are great natural growth enhancers that support your plants in many ways. They increase nutrient uptake, help establish healthier roots, and ensure all-around healthier plant development during all stages of growth. Not only do humic and fulvic acids result in greater yield potential, they can also be used no matter what type of grow-op you run, be it soil or hydroponics.


Most cannabis cultivators today use systems that are low in humic and fulvic acids. Some types of marijuana grows, like typical hydroponic setups, employ inert media such as hydroton or perlite, which do not contain any humic or fulvic acids at all. For soil grows indoors or outdoors, things do not look much better. Soil is most often depleted of these acids or contains only trace amounts. You can greatly improve the growing conditions for your cannabis plants by adding humic and fulvic acids to the equation.


Humic and fulvic acids work well together, with each providing its own benefits for better plant growth. Humic acid improves soil health and growth, while fulvic acid naturally facilitates your plant’s absorption and use of available nutrients.


Humic acids are complex acids resulting from the breakdown of dead organic material by soil microorganisms. They are dark brown to black in colour, and are soluble in alkaline water.

Humic acid has a high molecular weight, which makes it an excellent natural soil conditioner. It improves the properties of soil by supplementing and rejuvenating it. At the same time, humic acid improves availability, mobility, and management of nutrients in the substrate, and improves water retention.

What makes humic acid an excellent soil conditioner is its chelating ability; it attaches to micronutrients and forms a bond with them so that these nutrients can be more easily absorbed by plants. Humic acid also promotes improved ion-exchange and better soil buffering capabilities.

Humic acid actively allows for nutrients and minerals such as calcium, iron, magnesium, zinc, and manganese to be absorbed readily, stimulating improved plant growth and healthy roots. This works in any type of grow and provides benefits during all stages, from the seedling that just sprouted to mature cannabis plants.


Fulvic acid has a close relationship with humic acid, which is the reason why some refer to it simply as a “fancier” version. It is a humic material that is light yellow to brown, but unlike humic acid, is soluble at all pH levels—acidic and alkaline. Its molecular weight is lower than that of humic acid since it has less carbon but a higher oxygen content.

The lower molecular weight gives fulvic acid an excellent ability to cross the membranes of plant cells so it can easily penetrate into leaves. This makes fulvic acid particularly efficient when used as a foliar spray to provide nutrients to plants quickly. But you can also use it via irrigation by mixing it with your regular nutrient solution.

Furthermore, both humic and fulvic acid reduce the amount of nutrients that your plants need. For cultivators, this means healthy growth and excellent yields are achievable at a fraction of the cost.


Here are some of the benefits of using humic and fulvic acids for your cannabis plants:

  • Improves nutrient uptake and mobility via chelating action
  • Improves water retention and drainage of soil
  • Improves buffering capacity and cation exchange
  • Supports healthy microbial activity
  • Decreases plant uptake of toxins in soil
  • Improves photosynthesis
  • Boosts plant metabolism and cell division for better growth
  • Reduces amount of nutrients plants need


Cannabis cultivators can use humic substances in many ways. You can add them to your usual watering and nutrient regimen or use them as foliar spray. You can also add them to your soil in dry, powdered form.

Humic acid is available as a liquid or powder that you can dilute with water. This way, you can easily make a spray for foliar application. Apply the spray liberally to your plants’ leaves during veg, including the underside.

One other curious benefit of foliar-spraying plants with fulvic acid is that it can substitute for sunlight. It has been observed that foliar application of fulvic acid makes photosynthesis continue, even when it is overcast for a longer time period. Because of this effect, which is not yet entirely understood, fulvic acid is sometimes used commercially to rejuvenate green areas that are shaded.


Humic substances are available in various forms and in different concentrations. If you are not sure about what type to get, it’s recommended that you visit a reputable garden store in person, where the staff can advise you on the right type to get. They can also let you know about the proper dosage for your plants so you can avoid overdosing. Most of the time, it’s better to administer humic substances frequently, but in smaller doses. Always make sure you read the dosage instructions for your particular product.


Humic and fulvic acids are excellent to use together with a well-balanced nutritional program. They benefit your plants throughout all stages of growth, and can even save you money on nutrients. With the help of humic and fulvic acids, you can ensure that your plants are getting the most out of their available nutrients.

Learn how humic and fulvic acids can help take your cannabis grow to the next level. No matter if you grow in soil or hydro, these acids are super beneficial.

Why Humic Acid is Beneficial for Plant Growth

Takeaway: Just what exactly is that black powdery stuff growers are often asked to put in their soil, and how does it work? Here is master gardener Russell Landry with an explanation on humic acid.

Humic acid is often referred to as a natural plant-growth stimulator that increases plant metabolism and nutrient intake and improves plant development. These are pretty tall claims for any natural supplement; however, humic acid is one of the major components of organic matter found within nature’s most fertile soils.

Where can humic acid be found?

There are many types of natural humic acid amendment products used today, like this one from Monterey. They are often found in granular or liquid form and are dark brown. Humic acid and its cousins, fulvic acid and humus, can be found in most soils, marsh water courses, and boggy peat moss areas.

These organic compounds can also be found overlying the earth’s coal deposits (leonardite) in various forms and compositions. They are the end result of years of decaying plant organic matter that has been continually broken down by microbes from its prior humus forms.

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What is humic acid?

Humic acid is one of the best natural chelating products Mother Nature offers. It not only raises cation exchange capacity (CEC) or nutrient-holding capacity of soil, it also holds calcium and other micronutrients in forms that are easy for plants to uptake.

Humic acid contains numerous negatively charged anions that attract or hold onto positively charged cations in the soil. The cations growers are concerned with include a host of micro elements good for growing plants, with calcium, ammonium, magnesium, and iron among the most important.

This chelation of cations is probably the most important role of humic acid with respect to boosting plant production and fruit and vegetable yields. The CEC of the most popular brands of humic acid is in the range of 500 to 600 milliequivalents per 100 grams.

This is about five times greater than the CEC of high-quality peat moss and twice as high as the CEC of soil humus. Best results are obtained using natural ancient deposits of humus materials that are rich in both humic and fulvic acids.

What does humic acid do?

Humic acid also prevents calcium and other positively charged micro cations leaching from the soil by binding them to the soil’s molecules. It allows mycorrhizal fungi to flourish and easily colonize plant roots by providing nutrients in an easy-to-open storage bin.

The fungi easily garner and exchange other elements and thus share their required nutrients by transporting them directly into the root zone.

In the case of boosting yields, the increased uptake of nutrients is perhaps the greatest benefit of humic acid. In a sense, mycorrhizal fungi is the factory that processes the elements that are mined from the humic acid then shipped on the way to the roots assembly factory.

Although plant roots perform a similar job, fungi can tap into a wider reaching distribution network. Enhancing the products in the plant’s root system and network often results in increased yields.

Humic acid is ultimately a worthwhile investment when considering adding enhancements to your soil. It is one of the best natural sources of organic matter a grower could want.

Fulvic acid, humic acid’s cousin, is a more concentrated, smaller-particle form of the acid blends usually found in liquid form. It is referred to as a plant growth booster that increases plant metabolism and improves root development by also increasing nutrient intake.

It is naturally produced in soil by composting or after years of organic matter decay. Fulvic acid can rejuvenate soil and is an excellent supplement to fertilizers. It is also used to improve nutrient absorption and also to raise the CEC of soil.

Does adding humic or fulvic acid to your soil work? Drive by a nearby marsh or wetland and find out for yourself. Mucky soils found in marshy and low wetlands are often used to grow vegetables.

Marshy and swampy drained soils are rich in both acids and are some of the most productive areas on the planet. Thanks largely to the accumulation of the humic and fulvic built up in the soil over millennia, growers are able to easily boost their yields.

For those looking for a humic acid product, the good people at Monterey offer one at their website, here.

Humic acid is often referred to as a natural plant growth stimulator that increases plant metabolism and nutrient intake and improves plant development.