The Power of Ascophyllum Nodosum Extract in Cannabis Cultivation

The use of seaweed extracts in agriculture and horticulture has a history dating back thousands of years. However, it is only recently that the active ingredients responsible for making these extracts a valuable resource for plant growth and development have been identified and understood.

Seaweed extracts are particularly rich in natural plant growth hormones and beneficial trace elements, which makes them key components of many biostimulant products available on the market today.

The best seaweed extracts come from the species Ascophyllum nodosum, a brown alga that grows in mineral-rich waters such as those near Norway and Nova Scotia. Exposed to extreme conditions like temperature changes, flooding, drought, salt stress, and intense solar radiation, these algae develop high levels of hormones and protective agents (particularly auxins, cytokinins, and gibberellins) which are incredibly useful to plants.

Benefits of Hormones in Plant Development

Auxins, for instance, are produced in the leaves for then being transported to roots and growth tips to initiate crucial physiological changes, such as root formation. In horticulture, synthetic auxins are used in rooting powders and cloning gels to stimulate root growth. However, seaweed extracts contain natural auxins that, when combined with cytokinins, promote a larger root mass, thereby improving water and mineral absorption and strengthening the plant's resistance to stress.

Cytokinins are also abundant in seaweed extracts and play a critical role in rapid cell division and the formation of new cell walls. If applied just before the flowering starts, these hormones can also stimulate the development of more lateral buds, resulting in better flower and fruit production.

Gibberellins are also found in seaweed extracts. They are known for their influence on stem elongation and flower development, and also play a fundamental role in seed germination. By soaking the seeds in seaweed extracts before sowing, gibberellins activate dormant seeds to produce enzymes that break down the stored starches into energy, thereby facilitating germination.

Why Ascophyllum Nodosum?

Ascophyllum nodosum extract is rich in these types of hormones, as well as in a variety of bioactive compounds such as polysaccharides, amino acids, and trace elements. All of these make it a versatile biostimulant for various agricultural applications.

According to recent research, this extract can help in multiple aspects of plant development:

• Enhanced Root Development: Due to its content of natural growth hormones like cytokinins and auxins, it promotes robust root development, which improves nutrient and water absorption.
• Drought Stress Resistance: Ascophyllum nodosum improves the ability of plants to withstand drought conditions, which is crucial for maintaining crop health in environments where water access is limited.
• Growth Stimulation: This alga acts as a plant growth stimulant, increasing plant biomass and fostering more robust development, which is key to maximising cannabis production.
• Root-Microbiome Interaction: It also improves interactions between plant roots and soil microorganisms, promoting the colonisation of mycorrhizae. These symbiotic associations between fungi and roots are essential for improving nutrient absorption and disease resistance.
• Better Quality Flowers and Buds: By enhancing chlorophyll production, Ascophyllum nodosum can lead to higher photosynthesis rates. This translates into more energy for growth and flower production, resulting in denser and more resinous buds, which improves both the quantity and quality of the final product.
• Tolerance to Biotic and Abiotic Stresses: The compounds in this extract also help increase plant resistance to stresses like pests, diseases, and adverse weather conditions, reducing the need for chemical products and promoting more sustainable growing.

There are specific studies which demonstrate the potential of Ascophyllum nodosum extract to improve both productivity and fruit quality in tomato cultivation, when applied as a foliar spray in tropical environments. The extract appears to stimulate plant growth, stress tolerance, and fruit development through multiple mechanisms.

In some field experiments, for instance, foliar sprays containing 0.2 - 0.5% Ascophyllum nodosum extract significantly increased plant height (10 - 37%) and fruit yield (51 - 63%) in comparison to control plants. In greenhouse experiments, spraying with 0.5% of this extract increased plant height (20%), root mass (99%), shoot mass (38%), the number of fruit clusters (81%), and fruit yield (54%) in comparison to controls. 

The treatment also improved various fruit quality parameters, including size, colour, firmness, total soluble solids, and mineral/vitamin content, leading researchers to conclude that this alga offers clear benefits for improving tomato yield and quality in tropical growing conditions. This is likely due to its content of plant hormones, minerals, and other bioactive compounds.

Application in Cannabis Cultivation

Cannabis is a demanding plant that requires a perfect balance of nutrients and growing conditions. This is where Ascophyllum nodosum extract has proven to be particularly effective. By increasing resistance to water stress and improving root/microbiome interactions, this extract enhances the ability of cannabis plants to absorb essential nutrients such as nitrogen, phosphorus, and potassium, resulting in more vigorous growth and higher-quality flower production.

Additionally, the use of this alga helps reduce the need for chemical pesticides and fertilisers, aligning with organic and sustainable growing practices that many cannabis growers seek today.

It is interesting to note that, although the use of Ascophyllum nodosum is not always explicitly mentioned in the description of some growing products, this ingredient is the main active component in plant stimulators, such as those by Green Hope (specifically in products like Floramax and Rootmax). While Ascophyllum nodosum is not clearly specified in the technical data sheets of these products, this extract plays a central role in their formulation, contributing to the benefits observed in cannabis crops by maximising plant growth and resistance to adverse conditions.

In Summary...

Ascophyllum nodosum extract has become a powerful ally for growers looking to improve the quality and yield of their crops, including cannabis. Its ability to enhance stress resistance, promote growth, and foster soil and plant health makes it an essential tool in modern agriculture.

As more growers adopt sustainable practices, it is likely that we will see an increase in the use of natural biostimulants based on this marine alga, leveraging all its incredible potential to achieve healthier and more abundant crops.