The Science of Seaweed: Why it is a superfood for plants.
Ever wondered why seaweed makes a good natural fertiliser? Or how seaweed can bring life back to your plant? Or possibly, you’re new to being a plant/succulent owner or are expanding your plant/succulent fam and are looking for a natural, organic option to give them their best life?
We take a look below at the top five seaweed benefits for your plants and succulents.
1. Seaweed promotes protein biosynthesis through an abundance of amino acids and proteins
The proteins made from seaweed are high in content of unique amino acids at
approximately 10-30% of dry mass. As a macronutrient the levels of proteins vary
from species to species. This is a reason why each time we harvest we aim to collect
between 6-7 variations of seaweed species to create diversity in the nutrients we
provide with our liquid seaweed. Red algae’s carry the highest level of proteins,
followed by green algae’s and lastly the brown algae’s carrying the lowest level of
protein. Seaweeds are also unique in that they produce varying protein
concentrations with the winter and early spring providing the highest concentrations
of proteins. The growth phases of seaweed also influence the amount of protein
found in different species of seaweed.
Why are proteins and amino acids important for plants?
These nutrients are important for lots of different functions for plants including
photosynthesis, immunity, cell communication, transporting molecules, storage and
cell development. Although proteins in plants are categorised into 4 main protein
types based on their solubility using the Osborne Classification system, over 700
variations of amino acids exist and plants need a range of amino acids to carry out
these functions, with seaweeds having a balance in both essential and non-essential
amino acids.
2. Seaweed supports photosynthesis by providing all the essential nutrients for producing energy.
Photosynthesis is a sensitive process and if a flora species is missing an essential
nutrient the rate of photosynthesis slows, causing the energy produced, growth and
overall health of the plant to be affected. Nitrogen, phosphate, potassium,
manganese, zinc, chlorine, sulfur, copper, iron, magnesium and calcium all play a
part in process of flora photosynthesising and they can be found in liquid seaweed.
Starting with nitrogen, needed importantly and in large quantities, plants need this for
chlorophyl and protein function (including enzyme activity). Losing chlorophylls and
plant proteins stalls photosynthesis. Phosphates are used for two chemical
processes linked to photosynthesis, ATP and NAPD both involve the reduction and
movement of energy needed for flora to photosynthesise. Calcium also supports the
plants during ATP and provides additional structural support for the membranes
involved in photosynthesis. Potassium is only required in small amounts by a plant
and helps the guard cells adjust the stomata for carbon dioxide and water movement.
Chlorine also supports the guard cells in controlling the diameter of the stomata. If
the stomata remain fully open/closed water can be lost and carbon dioxide can be
restricted, slowing photosynthesis. Manganese again is needed in only small
amounts and is used by plants to split a water molecule, so it can use the hydrogen
to support the chlorophyll. Iron assists chlorophyll in the photosynthesis process by transporting electrons. Zinc provides an antioxidant element to the photosynthesis
process, likewise, sulfur transports electrons and is used by the plants to protect the
chloroplast membrane. Copper is also used by the plants to transport electrons and
is needed in small quantities. Magnesium is also linked to the chlorophyll and is
found within the molecule, supporting the making of proteins.
3. Another one of seaweed’s super powers is being able tobring life back to your flora, including cell growth and repair and metabolic pathways
We’ve touched on a few of the nutrients and elements that plants can benefit from
seaweeds. Seaweeds also help plants with repairing and growing cells and through
increasing metabolic pathways. A metabolic pathway is used by a plant to complete
its chemical reactions, taking molecules and inorganic substrates that cannot be
used yet by the plant, and going through a set of pathways to produce organic
molecules and products (metabolites) that can then be used by the plant.
How does seaweed help?
Seaweeds also contain various growth hormones. Most people probably would have
heard of the plant hormones auxins, seaweeds also contain cytokinin and
gibberellins that all have a part to play in stimulating growth for a plant. Auxins
specialise in triggering cell division within cells, leading to cell elongation, creating
growth. Cytokinin’s can be found in the roots of a plant and move to the shoot area of
the plant, signalling bud growth, creating denser, fuller leaves. Stimulating growth,
including seed germination and shoot elongation is the role of gibberellin hormones,
encouraging the overall health of the plant.
Metabolic pathways use three main metabolite groups, including phenolic groups
(simple sugars) terpenes (carbon and hydrogen) and nitrogen containing
compounds. They are then used by the plant to respond to changes in the
environment; to deter pests, protect the plant itself and attract pollinators. Seaweeds
naturally have an abundance of polyphenol compounds that regulate the role of the
metabolic pathways and also trigger fatty tissue to consume energy, acting as an
antioxidant and inflammation reducer for plants.
4. Seaweed naturally provides pest resistance and encourages soil fertility, Soil
balance and nutrient uptake.
Pest resistance
Plants experience many types of stresses living in their environment and usually
require chemical defences to help protect and enable them to survive. A common
stressor for plants are the invertebrates (aka pests) that enjoy taking a munch or two
(or even three) from them. Seaweeds produce natural pest resistant remedies that
can help land plants thrive too.
Seaweeds can reduce biotic stresses, including pests as they are naturally rich in
micro elements (e.g potassium and iron), vitamins and fatty acids. As mentioned
above, there are many chemical signals happening within a plant to trigger a
response to a stimulus from the environment. Specifically, researchers are finding
that iron availability in plants are important for cell signalling to stressors from the
environment. Plants respond to nutrients based on the availability of other
micronutrients. Having a balance of iron and manganese in plants balances their signals to enhance nutrient uptake (through electrons). Studies have found that
element found within seaweed improves the efficiency of mineral uptake and in turn
improves chemical signalling to respond to stress.
Soil balance and cycling
Alongside naturally repelling pests, Useful invertebrates in the soil take nutrients
found in seaweed and through cycling allows a healthy, balanced soil cycle to be
established. They say diversity is the spice of life and this rings true for the soil too.
An abundance of invertebrate species is an indicator of healthy soil. Recent research
has even suggested that we can hear healthy soil singing in the form of buzzing,
ringing and vibrating. These ‘tunes’ could provide farmers and gardeners in the future
an indication of the microorganism and fungal network beneath the soil.
How seaweed plays a role in soil cycling?
Seaweed does a fabulous job of creating soil stability and stimulating biological
activity, increasing microbial biomass. A happy, healthy soil system can cycle
independently, with a little maintenance required every so often. Seaweed supplies
the soil with nutrients for microorganisms to digest and change from an inorganic
form to organic matter that flora can uptake. This improves the aggregate within soil,
and the quality of soil aggregation will enhance root growth for flora, alongside
germination. Seaweed addition to the soil also improves the pore size and volume,
meaning that water, air and nutrients are able to move more freely and efficiently
through the soil to where it is needed.
5. Finally but not the least important, seaweed also plays a critical role in stable, strong, healthy root systems.
As touched on above, soil aggregation enhances root growth, their systems and secondaryroots. The ability for seaweed to stimulate root systems, is the presence and abundance of plant hormones (discussed above). These hormones stimulate and encourage cell elongation, cell division, stem elongation and seed germination, all essential processes for flora and their root systems. Alongside soil structure, seaweed application to the soil increases the activity of urease, phosphatase, glucosidase and sucrase and the availability for roots to uptake organic nitrates, phosphates and potassium. This in turn promotes root growth through soil layers, reaching deeper depths. Enzyme activity is also improved in the soil around the root systems by the addition of seaweed, protecting root damage from occurring. All of these factors promote and improve the physical structure of the roots, making seaweed a great addition for your flora.
If you would like to follow our journey, keep up to date with our projects and the latest in seaweed news, subscribe to our newsletter here. To read more about the history of seaweed read here or to read more about our sustainability responsibility to wild harvesting seaweed read here.