Top 5 Reasons Why You Need Kelp in your Cannabis Grow

Effect of Kelp on Plant Growth

Kelp is an array of massive brown algae (seaweed) that grows underwater and on rocky shores. Kelp is located in regions of the world with cold waters.

The benefits of marine kelp extract to plants have been identified through their active ingredients which include richly available plant hormones and beneficial trace elements (iron, copper, zinc, manganese, calcium, magnesium, sodium, sulfur and others).

The combination of these active ingredients makes the use of kelp extract an effective fertilizer and biological stimulant for enhancing better plant growth and development. The kelp extract from brown kelp Ascophyllum nodosum accumulated in mineral waters is known to be the best. Ascophyllum nodosum by nature develops within the littoral zone and is subjected to severe temperatures and varying intensities of sunlight. Therefore, it is exceptionally abundant in phytohormones (auxin, cytokinin, and gibberellin) and phytosanitary agents, and when subjected to stringent quality control methodologies, they become stable products.

Hormones are naturally found in plants to direct and regulate growth, development and other physiological processes in the plant. They are produced in a single part of the plant and transmitted to the other part of the plant, which is the site of action to cause physiological changes. Auxins are produced in leaves of plants after which is dispatched to roots and growing tips. Cytokines are supplied in the root and transmitted to leaflets and growth tips.

Some of the effects of kelp on plant growth are as follows:

  1. Bio-stimulation of germination and growth in plant

Kelp contains almost all micronutrients in the readily available form as well as plant hormones; all that encourages plant growth.

Kelp is also rich in carbohydrates that serve as plant material and also a source of food and energy for useful microorganisms in the root zone. The cytokine hormone mobilizes nutrients in plant leaves to improve the chlorophyll content, increase leaves, nodes, and buds. Also, kelp effectively supplements any nutrient deficiency and promotes additional budding sites when applied as a foliar spray after flowering begins during the flowering period.

Kelp additionally contains gibberellins with gibberane structures which are known for their impacts on stem elongation, parthenocarpy, bolting and flowering and at the same time essential for breaking seed dominance to induce germination. These effects are achieved when seeds are predominantly treated before planting by soaking seeds in liquid kelp extract.

  1. Increased Plant Immunity 

The kelp extract facilitates the absorption of nutrients and provides powerful plant hormones; this makes the plants healthier and more resistant to diseases. Kelp also contains natural antibiotic properties that can help eliminate harmful bacteria. These features also make seaweed good fertilizer, where antibiotic properties can help protect the leaves from infection and discourage pests. Seaweed extracts are particularly rich in cytokines. Cytokinins stimulate rapid cell division and production of new cell walls, so cytokines are particularly crucial for further growth. If cytokinin is used during vegetative growth, the plants will grow faster with stronger cell walls.

  1. Expanded and Healthy Root Zone 

Cytokines work together with other herbal hormones. If, for example, they apply cytokinin during root formation, the cytokines will stimulate the division of multiple root cells. Kelp solutions applied directly to the root zone enhances root, health, and vitality. Starch molecules similar to sponges found in kelp can retain water near plant roots for a long time, making moisture available to roots without saturation. These starches also help to enrich the soil by feeding beneficial microorganisms, bacteria, and fungi. Kelp also acts as a form of soil remediation by improving the overall structure of the soil.

  1. Fortifies Plant Development

Another essential feature of kelp is its rich concentration of vitamins; especially in the form of vitamin B. Vitamins provides the plants the power and energy needed to progress under the stress of accelerated growth rates. These powerful B vitamins can be particularly useful in cloning to reduce the mortality rate of vulnerable young plants.

  1. Increased Yields

The most prominent visual effects of kelp fertilizer will be visible at harvest time. Rich content of stimulants, enzymes, and nutrients will generate more abundant flowers, fruit, and vegetables. Cytokinins applied just before flowering aid the formation of more lateral buds which will help in the overall yield and quality of the budding plants.

 Kelp as an Ingredient in our formulas

The wonderful effects of kelp on plant growth are evident, with many studies publicly attributing to their effectiveness in agricultural applications. With this understanding, we've formulated products with kelp in them already to help in maximizing plant growth while saving the growers the expense of having to buy a separate kelp additive. Some of our products you can find kelp in are: Omega Grow and Omega Bloom formulations, Beta Balls a microbial booster and trace mineral granule, as well as in MycoRhize, our 12 species mycorrhizae inoculum. By using these products and incorporating them into your regiment, you won't have to go out and buy kelp separately since these formulas utilize large amounts of kelp in them already.




Ali, Nerissa, et al. “The Effect of Ascophyllum Nodosum Extract on the Growth, Yield and Fruit Quality of Tomato Grown under Tropical Conditions.” SpringerLink, Springer, Dordrecht, 12 May 2015,

“Plant Hormones and Their Role in Plant Growth and Development.” 1987.

Thorsen, Maja K., et al. “Kelp (Laminaria Digitata) Increases Germination and Affects Rooting and Plant Vigour in Crops and Native Plants from an Arable Grassland in the Outer Hebrides, Scotland.” SpringerLink, Springer, Dordrecht, 26 Feb. 2010,

Zheng, Shiyan, et al. “Effect of Kelp Waste Extracts on the Growth and Development of Pakchoi (Brassica Chinensis L.).” Scientific Reports, no. 1, 2016.