Seaweed tonic - it's not your average fertilizer! - NativeNeem

Seaweed tonic - it's not your average fertilizer!

Seaweed tonic: Not your average garden fertilizer!


If you have a green thumb, it’s likely that you’ve heard about Seaweed Tonic. It’s an all-natural plant and soil conditioner that has been around long before the use of commercial fertilizers, used frequently in the gardens of those that prefer organic methods to produce their bumper crops.

The benefits of Seaweed tonic are much more than providing nutrients, it helps to grow plants that are healthier and more robust, improving their resilience to environmental stressors and pests.


What exactly is seaweed tonic?

As the name suggests, Seaweed tonic is made up of harvested Seaweed (species like large brown kelp are often used) that once collected is left to ferment in water until all the plant material has broken down and become a liquid.  

The resultant dark brown, pungent liquid has been used for many years by home gardeners and in commercial agricultural practices to help improve the health and yield of plants.

Because seaweed is a renewable resource and the natural fermentation process requires no additional chemical input (like conventional fertilizers), it has a low impact on the environment. As sustainability is a growing worldwide trend, seaweed tonics are becoming more widely available and frequently utilized in home gardens and commercial agriculture.


How does it help plants?

Seaweed tonics are much more than a nutrient delivery system (like traditional fertilizers), they work to increase the health of plants and the soil in which they are grown in several unique ways:

  • The nutrients extracted from the natural fermentation process are in a form that is readily and easily absorbed by plants. This isn’t always the case with standard fertilizers, as some can only be applied to soil. Whereas seaweed tonics are able to be applied to the foliar/leaves of the plant which is ideal for nutrient uptake.
  • Seaweed tonics help to reduce nutrient leaching from soil and plant root zones. This typically occurs with heavy rain or irrigation, where important nutrients are washed away from where the plant can access them. The beneficial microorganisms in seaweed tonic, a biproduct of fermentation, create a ‘sticky’ substance that help to bind nutrients to the soil particles of the root zone. Holding them in the area that is readily available for uptake.
  • Help to strengthen plant defences. It’s similar concept to boosting their immune function, making the plants healthier and hardier to different environmental stressors like drought, wind & rain.
  • Seaweed tonics improve the condition of soil, thanks to a naturally occurring seaweed compound called alginate. This is a structural part of seaweed cell walls that help to give them flexibility to withstand tidal forces. When applied to soil, alginate acts like a conditioner and creates bigger soil particles that improve the movement of water and air.




Components of seaweed tonic

Seaweed tonics are made up of a number of different nutrients, but also important compounds such as growth hormones and bio stimulants.

  • Nutrients: a broad spectrum of macro- and micro-nutrients as well as trace minerals to meet all of the nutritional needs of growing plants. Specific for plant growth is the presence of NPK (nitrogen, phosphorus and potassium) and is in a form that is readily available for plant uptake. Potassium plays a role in increasing a plants overall hardiness to withstand harsh elements and protect against pathogens and disease.
  • Growth hormones: phytohormones regulate evey aspect of plant growth and development. There are 5 phytohormones found within kelp, and fermented seaweed tonics, that work together or independently to help support growth cycle of the plant. These 5 phytohormones are auxin, cytokinin, gibberellin, abscisic acid and ethylene. When they are given supplementary, a plant can focus all its energy on growth as opposed to creating the hormones itself.
  • Amino acids: similar to their importance to the human body, plants also require amino acids for the building blocks of their structure and metabolic processes. They are also important for soil microbes, to increase the strength and growth of microbial colonies. Healthy soil microbes help to protect the health of the plant and support nutrient uptake from plant roots.
  • Beneficial bacteria & fungi: soil microbes like bacteria and fungi live in symbiosis with eachother and the plants growing around them. They help to stimulate root growth, produce growth hormones and metabolites that protect against fungal disease. Fungi also improve utilization of water by plant roots.
  • Bioactive carbohydrates: polysaccharide carbohydrates from seaweed play a key role in activating plant defence mechanisms that help to protect against harmful pathogens.


Native Neem’s Organic Neem and Seaweed Tonic

Our BioGro Organic Certified plant tonic is a combination of Organic Neem oil and fermented seaweed extract. This blend of natural extracts provides plants with a full range of essential nutrients, growth hormones, protein and carbohydrates that are needed to boost overall health and growth. Being a liquid formulation, plants are able to easily absorb and readily utilize the nutritional benefits straight from their foliage (if sprayed directly on the plant). With the added benefits of Organic Neem oil, an extra layer of plant protection is provided as Neem Oil acts as an effective deterrent to a wide range of pests and bugs.


When to use

  • During a plants active growing season. It is important to let a plant naturally slow and enter dormancy during colder winter months, so focus application on main times of growth.
  • Soaking seeds in diluted seaweed tonic can help improve germination rates and early root growth.
  • When repotting or planting out from a container, spray plant or soak roots to help reduce risk of transplant shock.


For exact quantities for use and dilution rates, refer to our website or directions for use on product label.

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