The Natural Synergy of Biostimulants, Salts and Microbes

Reintroducing Natural Symbiosis to Your Hydroponic Growing Operation

Natural Biostimulants‘ vs ‘Plant Growth Retardants‘: “How Do These Treatments Alter Plant Metabolism?”

The developmental impact of PGR or ‘Plant Growth Retardants’ in the context of 1-2 weeks of a plant’s life can be compared to an entire decade of a human existence. This is based on how some cannabis plants live for only roughly 3-4 months, whereas an average human can live up to 70 years.

Using PGR for even a couple of weeks let alone using PGR base nutrients throughout the entire growing process — is the equivalent of human shooting up dodgy steroids and hormone treatments for many years of their life.

Biostimulants are a natural alternative to Plant Growth Retardants. They can be found in extracts — or produced by microbes that colonise the roots of the plants.

Much like PGRs, Biostimulants alter the metabolic expression of plants… yet, unlike dangerous Plant Growth Retardants, they’re organic and non-toxic. Acute headaches, lowered fertility and chronic liver failure are just some of the documented effects of consuming PGR-treated cannabis via smoke inhalation. Cannabis grown with natural Biostimulants do not produce these symptoms when consumed by humans.

Natural Biostimulants make your buds fat, without leaving nasty chemicals infused into your bud. They work in synergy with the natural chemistry of your plant; symbiotically utilising the root systems and microbes, which empowers your plant to focus its energy on growing big and strong.

The end result is almost always a more robust, disease-resistant plant, which produces bigger, healthier fruits in flower.
- Advertisement -

What Your Plant Wants

Biostimulants align with natural design — which often aligns with our goals, too:

  • Plants want larger fruit/bud to carry more seeds, so they may pass on their genetics through a solid seedstock.
  • Plants want larger and more vibrant, aromatic flowers to attract pollinators (such as bees, which collect pollen from various plants as food, but leave as little behind on each as well).
  • Plants want higher quality oils, resins, and aromas to attract good bugs and repel bad bugs.
  • Plants want firm, sturdy stems to support great growth and heavier yield while being resistant to weather.
  • Plants want more minerals and stimulants to help resist pests and disease.
  • By assisting metabolism and providing nutrition, less energy is spent by the plant..

Natural Biostimulants

Australian Cannabis University Outdoor Grow

There are seven key Amino Acid chelators (23+ aminos are recognised).

Natural Biostimulants work in deep harmony with microbiology in the rhizosphere of the plant. Amino Acids, Humic/Fulvic Acids, and Silicic Acid all help the plant focus its energy on producing bigger, better fruits.

Several of these Amino Acids are involved with influencing the plant’s genetic expression, or ‘phenotype’.Amino Acids aid nutrient uptake, as non-overly aggressive chelators. They also provide an organic source of Nitrogen, and prevent limescale in nutrient reservoirs and lines. Amino Acids add Nitrogen to the NPK ratio.N exists latent in the structure of Amino Acids.

Nitrogen deficiency.

Amino Acids can increase pathogen resistance and chlorophyll production, stimulate vitamin production, stimulate fruiting, and increase the nutrient content of your fruit.

LForm Amino Acids are produced organically by microbes. Enzymatic Hydrolysis (or ‘protein hydroxalytes’) are key to producing plant active L-amino acids.

Glutamic Acid and Glycine are responsible for opening Ca channels and flooding the plant with Ca.
A combination of Auxin + Cytokinin helps with lateral root growth and water uptake.

Cytokinin used as a foliar spray helps increase break apical dominance by encouraging lateral growth and tight, even bud development. Cytokinin acts as a plant protection agent by sponging free radicals, protecting the plant’s cell membranes with Humic Acid. This allows them to handle and recover from various kinds of stresses.

Calcium contributes to strong fungal and heat resistance by flooding the vasculature of plants.

Calcium is also primarily responsible for the production of strong, tight plant cells in new plant tissue. Acting through the plant’s vasculature, Calciumosmotically holds water in the plant; reducing leaf tip necrosis (leaf burn) from excessive heat and/or salt build-up. This effect also acts as a desiccant to any fungi inside.

A stronger uptake of Calcium leads to stronger development of the vasculature system and higher levels of minerals + ‘brix’ (or sugars). Increased Calcium also fuels increased Pectin binding.

Silica is only immediately available to the plant in monomer form, as an organic acid.

Silica aids nutrient uptake, and the formation of strong cell walls.

Fe and Mn are responsible for producing many ‘medicinal’ compounds in cannabis plants.
Tryptophan is another Amino that is turned into IAA; a growth hormone in the plant.
Gibberilic Acid is great as a seed soak (especially in the case of older seeds) for improving germination speeds.
Cysteine ‘turns on’ specific genes in the plant to make them focus on fruit producing areas, rather than stems and leaves.

Once you activate a plant with Cysteine, the effect can be maintained with small maintenance doses.

Humic and Fulvic acids are intermediate chelators, which entail a different process to Amino Acids.

Fulvic Acids aid with Iron and trace element uptake; especially in combination with Humic Acid.

They also act as a pH buffer via stimulating H+HTPase to negatively charge the inside of membranes, aiding the flow of positively charged plant nutrients into the plant.

Kelp Extracts are best used in a 5:2 ratio with Humic Acids.

Carbohydrates are microbe food. Microbes ARE the Biostimulant.

Microbes make organic acids that aid with trace element uptake. They also turn carbohydrates into enzymes, organic acids, amino acids, B vitamins, and increase root surface area and nutrient uptake.

In flower — especially towards the end — the plant hoards carbohydrates. In this stage, use complex carbs.

B Vitamins are also important.

B1 induces systemic resistance, which can last onwards from its dose. Systemic resistance is a plant immune system that can help fight any pathogen.

B1, B2, B3 and B6 stimulate production of natural Biostimulants and sugars; boosting the metabolism of the root microbes, which encourages root development.

Yucca is a natural wetting agent that keeps organic molecules and minerals in suspension with each other.

Water disperses through the root zone with Yucca much better than usual. Yucca also contains saponins – a natural fungicide, especially when applied as a foliar.

Brix – What is it?

Use of Biostimulants leads to higher Brix levels.

Brix is the most widely used and accepted measurement throughout agriculture in terms of determining quality and ripeness of fruits. This is a measure of the sucrose, amino acid, vitamin, phytohormone and mineral levels within the plant’s vasculature (a liquid solution).

In cannabis, Brix levels directly relate to the % of cannabinoids, relative to genetic potential. Increased Brix acts as a repellent for disease and pests, like spider mites.

The ‘Nutrient Cascade Effect’

It is important to understand that plants have a defined biological sequence of nutrient uptake.

They need a baseline of nutrition, with all nutrients present, at all times — without a weak link. Calcium is involved early in this sequence. Deficiency in Calcium commonly limits the uptake of other nutrients.

The nutrient sequence of cannabis starts with Boron, which makes the root system disperse sugars into the medium. These sugars feed the microbes, which transform silicates (Si) into Silicic Acid, which stimulates Calcium uptake.

Classic Boron deficiency.

These elements should be present in a bioavailable form to plants at all times, as the plant requires. If one nutrient in this sequence is less available, the uptake of all other elements in the sequence will prove more difficult.

Maintaining a balanced spectrum of nutrients in the medium is important. Spiking certain nutrients at certain times of the grow will assist you in achieving your end result.

Common Salt Antagonisms

Inorganic N / High Nitrate Antagonises Calcium

Overfeeding inorganic nitrate-based Nitrogen leads to big cells with thin cell walls. This attracts disease and reduces brix value of your end product, due to the plant burning more energy in other areas comparatively to a plant with healthy, smaller, thicker-walled cells.

Nitrate build-up directly antagonises Calcium uptake through the plant’s roots, which can cause immediate issues, as Ca is immobile. The result is decreased fungal resistance and general resilience.Ca is critical to healthy vasculature and strong cell wall formation.

Potassium (K) Antagonises Nitrogen (N) + CaMg

Magnesium deficiency.

Using too much mono PK spiked flower booster from the start to the end of flower can have significant negative effects. This locks out Nitrogen and CaMg when it is needed the most — in early to mid flower. Nitrogen use peaks at weeks 2 – 3, with Calcium use peaking at around weeks 4 -5.

Your plant needs very little extra K until weeks 5 – 8 in flower. Using PK boosters excessively throughout flower can cause significant negative effects, via K antagonisms in early to mid flower.

Phosphorus (P) Antagonises Zn, Fe, Cu

Overdosing your plants with Phosphorus can lock out important immobile micronutrients, causing immediate grow issues… like locking out Ca does. These issues are just not always as immediately noticeable or severe.

Too much Phosphorus can also increase Nitrogen intake. Phosphorus needs a spike between weeks 2 – 8.

Calcium (Ca) Antagonises Boron (B), Magnesium and Phosphorus

Magnesium deficiency.

Ca, N and P all being taken up together and not locking each other out is a big part of your buds stacking properly in early to mid flower. Providing — but not overdoing — eitherCaorP is important… particularly CaMg, as those products are typically high EC.

Ca build-up can also lock out Boron, which holds a critical role in initiating the ‘nutrient cascade’.

Mg Antagonises Ca, K

CaMg products should be balanced enough to prevent this… but an overuse can lock out P in early to mid flower (via Ca build-up) and lock out K in late flower (via Mg build-up).

Sodium (Na) Antagonises K, Ca, Mg

In some cases, tap water might contain enough Sodium that it can reduce availability of some fairly important nutrients… that is, if your medium is not flushed enough over time. Na is not really needed at all by the plant… so, it will build up in the medium over the process of the grow.

Ammonium Antagonises Ca, Cu

Don’t pee on your plants for Nitrogen. Acidic environments promote increased Ammonium levels. Not good.

Sulfur (S) Antagonises Molybdenum

Some booster products and Epsom salts can have high Sulfur levels. If you’re using several **Sulphur-**containing products at once, the resulting overfeed build-up can have negative effects. Correct application of Sulphur is important to maintain the taste and smell of your end product.

CaMg Supplements

Calcium is a natural fungicidal desiccant, when concentrated within the plants vasculature. It contributes to heat resistance, increases plant vigour and stem length. It assists with post-harvest shelf life and mould resistance, too.

Nitrate build-ups serve to antagonise Ca from being able to enter your plant’s cells. This is why high levels of inorganic Nitrogen in the rest of your feed program could be potentially harmful. You will find high levels of nitrates in AB and CaMg products. Flush often.

Further, build-up of Ca or Mg separately can antagonise each other directly.

A product with a good ratio of Ca to Mg, with minimal relative nitrate content, is most desirable. Calimagic and Grotek CalMag are two good options.

Coco coir has cation exchange sites that naturally contain Na and K. These will preferentially pull in Ca and Mg, releasing Sodium and Potassium.

Prebuffering will strip the Na and K from Coco and ‘charge’ the medium with Ca and Mg — rendering coco as a neutral medium for nutrient absorption.


Coco will continue to break down over the grow, exposing new cation exchange sites that will require Ca and Mg to strip Na and K. This is why coco needs both pre-buffering, as well as increased ongoing CaMg use… and slightly reduced K use.

Troubleshooting: What Deficiency Do I Have?

Nutrient deficiency can be a result of many factors: salt buildup, pH swings, poor root health or underfeeding are very common culprits. Where complete coco AB feeds are used, underfeeding tends to be a less common cause of deficiency.

Mobile Nutrients

NPK, Mg and S are all mobile elements. Deficiency will always start at the bottom of the plant, moving as the plant sucks the chemicals upwards.

The stages of Phosphorus deficiency.

A specimen with a Potassium deficiency.

Nitrogen deficiency is a classic general yellowing of leaves from the bottom up. Sulphur deficiency can appear similar, but is less common. Phosphorus will show up with spotty-leaf necrosis.

Potassium-deficient plants will display symptoms of leaf-edge necrosis from the bottom-up. Magnesium creates an interveinal dechlorosis (yellowing between veins) from the bottom up — a classic form of mobile nutrient deficiency.

Other nutrient deficiencies tend to create various patterns of spotty-leaf necrosis from the bottom-up.

Calcium deficiencies typically show up with brown spots on new growth.

Immobile Nutrients

Calciumand the other micronutrients are all immobile.Deficiency will cause immediate issues on the newest plant growth.

Other micronutrient deficiencies typically show up as interveinal dechlorosis on new-but-not-old growth. Alkalinisation of the grow medium is a common cause of micronutrient uptake issues.

Dying Leaves

This can be a result of natural fading in late flower… or it could be due to extreme salt buildup, pH swing, dry heat, poor Calcium/Silica uptake, and/or flushing too soon, before harvest in flower.

Do some problem solving before assuming a cause — similar things can happen visually for just about opposite reasons. Inadequate nutrition from lockout (salt/pH issues) or flushing will lead to leaves falling off from the bottom-up, as the plant cannibalises itself for nutrition. There can be mild-to-moderate issues on new growth due to immobile nutrient deficiency. Later in flower, bud growth can be stunted by a lack of immobile nutrients, while the leaves around it still appear to be okay.

Remember that airflow through the plant, often in the lower/mid leaves, will exacerbate leaf health issues.

Excessive heat, light, dryness and Ca/Fe lockout will lead to leaves taco-ing, burning and dying from the top of the plant — generally on the newer growth.

Basic Problem Solving

  • Is your EC draining out, less than going in (i.e. is your medium not building-up on salt)?
    • If your EC drains out higher than it goes in, nutrient uptake problems are likely a result of salt antagonism and pH swings.
      • Canna-based nutes are designed to be used with tap water at 0.4EC.
    • Coco coir has only a moderate ion exchange capacity, and salt buildup will quickly compound and greatly reduce nutrient uptake. I recommend flushing with enzymes/acids until runoff EC is half the previous input EC.
      • Once runoff is back down, give a feed of microbial, stress relief and/or enzymatic biostimulant products.
      • It’s recommended to hand-flush coco weekly on top of the regular fertigation schedule, to help minimise salt antagonisms.
      • Once flushed, adjust feed based on likely buildup (often, there’s too much AB).
  • Is your deficiency mobile or immobile, or on new or old growth?
    • Damage on mid growth can be pest/pathogen related, or from a previous corrected immobile nutrient deficiency.
  • Are you pHing input?
  • Have you properly calibrated your pH pen + cross referenced with pH drops recently?
  • What is pH of immediate drainage?
    • With accumulated drainage, pH naturally swings to 7 over time.
  • What are you feeding? What is the plant using at this stage in life? Have excess nutrients built up in your medium?
  • How does your environment compare to ideal VPD conditions?
  • What issues are common in your medium and grow environment, historically?
  • Have you made changes to your routine?

The ‘Rhizosphere’ — Bacteria and Fungi


Carbon is an anchor for Bacteria in your medium. *Charcoal, organic acids (*amino acids, humic acids, silicic acids etc) and organic matter act as sources of Carbon, which maintains microbial life.

Bacteria feed primarily on instantly available simple sugars… but they can also process complex sugars over a longer time period. Sugars give Bacteria the energy to perform a range of functions:

  • Bacteria produces hormones, enzymes, auxins, saponins, vitamins, amino acids and other‘Biostimulants’.
  • Breaks down and stores nutrients for later use.
  • Converts unusable salts into plant-available forms.
    • Breaks down organic matter via enzymatic action.
  • Certain species can fix atmospheric Nitrogen to make available for the plant as needed
  • Bacteria can increase/alkalinise pH of the soil over time (via waste products), leading to increased immunity from disease, and reduced ammonium content of the soil.

Fungi – aka mycorrhiza

Fungi attach to root hairs, forming a casing around the plant cells. They also covert and transport nutrients into root tissue. In comparison to Bacteria, Fungi often take longer periods of time (weeks to months vs. days) to become established on the roots.

Fungi tend to perform better with larger, more complex molecule food sources; yet, they are still able to consume simple sugars relatively quickly. They break down larger sugars via enzymatic action for food.

For growing with fungi, check outmycogold a complete mycorrhizal fungus for your medium.

Fungi act to:
  • Decrease/acidify soil pH
  • Feed on and break down complex organic matter into useable plant nutrition (via humification).
  • Create hyphae networks that transport nutrients through your medium; and into the rhizosphere, where it can be taken up by the roots.
  • Fungi pulls nutrients into root hairs; protecting them from pathogens and pests via root biofilm.
  • Fungi increase root surface area, increasing moisture and nutrient uptake around the roots.
  • Release stored N as ammonium
  • Some Fungi can grow inside plant tissue ****and protect against more harmful Fungi, like Powdery Mildew.

Contributions by Mick Hardwood. Edited by Mitch.


Dr Harley Smith on biostimulants, the links to microbes, and dutch research –


Author: Mitch

Mitch Keys is a young writer from Brisbane, Australia unfolding in a dynamic process of becoming (like everyone else, so don’t go thinking he’s special or anything). He likes being alive.

Mitch Keys is a young writer from Brisbane, Australia unfolding in a dynamic process of becoming (like everyone else, so don’t go thinking he’s special or anything). He likes being alive.


Notify of
Inline Feedbacks
View all comments

[…] The Natural Synergy of Biostimulants, Salts and Microbes […]


[…] Recommended For YouThe Natural Synergy of Biostimulants, Salts and Microbes […]

Would love your thoughts, please comment.x