BioTabs cannabis nutrient feeding guide

13/10/2023

BioTabs nutrient feeding strategy for cannabis

Over 3 decades experience selling cannabis seeds has shown Dutch Passion that perhaps the most common error by cannabis growers is over/under feeding their plants with mineral nutrients. The result is restricted growth with under feeding or stunted growth (with ‘burnt’ leaf tips) when over-feeding.

In both cases harvest size and quality are reduced. If that sounds like a familiar issue in your grow room then you may be relieved to know that slow-release organic nutrients such as those from the market leader (BioTabs) are the easiest way to keep your plants in the nutrient ‘sweet-spot’ (without over or under feeding).

Many growers have seen their grow room results completely transformed once they replaced their traditional nutrient regime with slow release organic BioTabs.

Growing cannabis the organic way with BioTabs

The main advantage of slow-release organic nutrients is that their nutrients are slowly released over the period of your grow, providing a steady stream of nutrition. Cannabis macro nutrients and micro nutrients are included to ensure your plants don’t see any nutrient/mineral deficiencies. BioTabs contain many beneficial microbes and fungi that naturally improve soil health.

Over a controlled period, the organic nutrients are broken down naturally and at a controlled rate which matches your plants nutritional needs. This frees the grower from the burden of accurate dosing using their traditional mineral nutrients. Instead, all you need to do is add water and leave the difficult work to the BioTabs. What could be simpler? You won’t need to worry about pH and E.C. again!

Growers that hate seeing brown, burnt leaf tips from over-feeding will find slow-release BioTabs permanently remove that pain. Cannabis plants thrive with great vigour when given optimised nutrition, allowing new levels of quality/potency and maximised harvest quantities.

If you find cannabis cultivation a little more demanding and complicated than you would like, and if mineral nutrients have tested your patience from time to time, then BioTabs can completely transform your grow experience.

BioTabs “classic strategy” nutrient feeding guide

BioTabs “classic strategy” nutrient feeding chart

In most cases, even for experienced growers, BioTabs deliver superior consistency by reducing complexity and giving you a wider grow latitude. The various BioTabs slow-release additives are mixed into the grow soil or coco fibre (they are not suitable for those growing with cannabis hydroponics, due to risk of pipeline blockages). When the grow starts, the grower simply has to add water when required.

The only time you may need to give additional nutrients is in late/middle bloom. Often all that is required (if anything at all) is a touch of bloom nutrients in late flowering if the plants seem hungry. This can be done with the Bio PK or a PK enriched booster tea.

It’s important to add that slow-release organic feeding using BioTabs isn’t merely an option for the anxious rookie grower. Plenty of expert growers have reached connoisseur quality levels in their harvested buds because they switched to BioTabs.

The costs of BioTabs are similar to those of traditional mineral nutrients, but their ease-of-use is dramatically superior. Once a grower has experienced the simplicity of growing with BioTabs, few switch back to mineral nutrients.

BioTabs have decades of experience with slow-release organic nutrients. Their current product line-up has never been better and benefits from a complete range of organic additives that are proven to give a controlled continual release of nutrients and beneficial microbes into your soil.

If you find mineral nutrient usage leaves you on a permanent knife-edge between over/under feeding then now could be time to consider slow-release organics.

Here’s a quick look at the BioTabs range and how to use them:

Startrex	An initial soil conditioner with organic nutrients and beneficial bacteria.
Mycotrex	A concentrated shot of 9 different beneficial soil fungi.
BioTabs	Slow-release fertiliser tablets which you bury in the grow medium.
Bactrex	Beneficial soil bacteria with Trichoderma genus mold soil microbes, which help convert organic matter into a steady stream of nutrients.
Orgatrex	Organic liquid fertiliser with a 5:1:5 NPK ratio.

Using BioTabs couldn’t be any easier, requiring just a couple of minutes of effort to mix the ingredients into your soil/coco fibre mix. Once that is done, you can look forward to a simple grow where all you need to do is add water.

Soil preparation

Most experienced growers prefer to use large plant containers in the region of 15-75 litres. One advantage of this approach is that your plants enjoy a large, difficult-to-exhaust, reservoir of nutrients and moisture. When using larger containers (e.g. 30-50 litres) of soil you probably won’t even have to worry about adding any additional bloom nutrients towards the end.

Use a large ‘trug’ style garden container (e.g. 100 litre) to thoroughly mix all the BioTabs additives into. Once the mixing is complete simply place the mixed soil into your airpots/felt-sacks. The appropriate number of BioTab fertiliser tablets are added (according to container size) and pushed 5cm below the soil surface.

Now it’s time to prepare the soil with the right levels of microbial activity. In 1 litre of water add 1g (a level teaspoon contains 1g) of Bactrex and 5ml of Orgatrex. Shake well and water your soil with the liquid.

Now it’s time for the cuttings, seedlings, cannabis seeds or germinated weed seeds to be placed in the grow medium. Make a small depression and sprinkle 5g of Mycotrex into it (5 level teaspoons). The fungi powder can be sprinkled inside the hole where you will place your cannabis seed or cuttings.

Seedling stage

Just add water when required. No need to add anything for the first 4 weeks. The Dutch Passion guide to cannabis seedling growing may be useful background reading.

Vegetative stage

After 5 weeks it’s time to boost soil health. For each plant, use 500ml of water with 20ml of Orgatrex and 1g (1 level teaspoon) of Bactrex. From here onwards the high levels of beneficial microbes and fungi continuously break down organic matter producing a steady flow of minerals and nutrients available for root absorption.

If growing in soil all you need do subsequently is add water, no need to check pH or E.C. (electrical conductivity). If you sense that the plants are running out of nutrients you can feed them easily. Simply take 1 litre of water, add 5ml or Orgatrex and 1 gram (1 level teaspoon) of Bactrex. Note that the Orgatrex is a slow-release feed, you won’t ‘burn’ your plants instantly since the nutrients are released slowly and progressively.

Flowering stage

Continue to feed with water. If plants need additional feed then use the principle above. Feed with 1 litre of water with 5ml of Orgatrex and 1g (1 level teaspoon) of Bactrex. Those growing in larger containers will benefit from a greater reserve of soil-based organic matter and nutrients. Growers using larger grow containers are therefore less likely to need to add additional feed in bloom.

Slow-release BioTabs: autoflower seeds vs photoperiod feminised seeds.

You can grow autoflowering cannabis seeds or photoperiod feminised seeds using BioTabs. The slow-release nature of the nutrient delivery is equally suited to growing either form of cannabis seed.

BioTabs “just add water strategy” nutrient feeding guide

BioTabs “just add water strategy” nutrient feeding chart

The BioTabs organic grow manual explains the simple process of how to use slow-release organic nutrients. The beauty of BioTabs lies in the simplicity and the lack of scope to over/under feed your cannabis plants. The result is perhaps the widest-latitude grow system available. Follow the recipe and you really can’t spoil your grow by yoyo-ing between over-fed and under-fed plants.

BioTabs always provide thorough technical information about each of their products. Here are some bonus tips for those keen to move away from mineral nutrients to the easier BioTabs approach.

With an NPK ratio of 4-3-3, Silicium Flash is a quick release fertiliser and soil improver. This is often used by more experienced BioTab users with quick-release nutrients should they ever be required. But it also contains slow-release nutrients which will continue to deliver Silicon, Nitrogen, Phosphorus and Potassium.

Silicium Flash can be used sparingly when preparing the growing medium or for treating nutrient deficiencies. Silicium Flash increases the plant’s resistance to heat, drought, pests and disease/pathogens. It works by boosting nutrient absorption – producing stronger plants with higher yields.

Silicium Flash can be added near the plant stem (create a small depression and add 25g, covering with soil). For mother plants, add 100g to the soil and repeat every 2 months or so. Silicium flash can be sprinkled on the surface soil as a ‘top dressing’ or in small holes near the stem.

Startrex is an organic soil improver with an NPK ratio of 3:1:2, it contains high levels of probiotic bacteria which help revive/improve soil quality. Startrex is formulated with micro-organisms to improve the health of your soil at the start of the grow and contains Silicon and Fulvic acid.

A 20-litre plant container requires 100g of Startrex, a 50-litre container requires 250g. The powder is simply manually mixed into the soil. The BioTabs instructions show the necessary dose of Startrex (and other BioTabs additives) for your particular plant container size.

Pro Tip: Use of highly aerated grow containers such as air pots, auto-pots or felt sacks are particularly recommended due to the increased levels of oxygen which can reach the root mass. Also recommended, particularly for auto-pot growers are air-domes.

These are placed at the bottom of your grow container and connected to an air-pump. The principle is simple and popular with many coco-growers, delivering additional oxygenation at root level, boosting growth.

Mycotrex is a blend of 9 different types of beneficial fungi which help cannabis roots absorb nutrients. It is certified to be fully organic and can be used by both indoor and outdoor cannabis growers where the mycorrhizal fungi can boost mineral uptake by up to 700%.

BioTabs are the palm-size tablets made from compressed, blended organic matter. They slowly breakdown in the soil releasing their nutrition.

They are usually placed 5cm below the soil around the plant with an NPK ratio of 15:7:8 and fertilise the soil as well as conditioning it with beneficial soil bacteria. They work in coco or soil, indoor or outdoors. The instructions indicate how many BioTabs to add according to the container size.

For a 10 litre container you would use two BioTabs, a 20 litre container requires three BioTabs and a 50 litre container requires four.

Bactrex is a concentrated blend of beneficial bacteria with Trichoderma genus mold soil microbes essential for soil health and bioactivity. It provides excellent protection from root pathogens and improves soil health – converting organic matter into nutrients.

Bactrex can be used to protect recently rooted cuttings or germinated seeds against pathogens including pythium. It is a powerful organic soil improver. Use one level teaspoon per litre water. One litre will treat 50 cuttings or seedlings and is good for soil or coco fibre, indoors or outdoors.

Bactrex is supplied as a dry, water-soluble powder.

It contains a large number of beneficial soil bacteria and root microbes (including 6 strains of Bacillus spp.), Trichoderma fungi and actinomycetes. These beneficial fungi & bacteria are selected for their positive effect on soil structure and fertility. The specialised root bacteria come in a soluble Yucca extract with organic catalysts. These guarantee a rapid colonisation and growth around the root zone.

Trichoderma’s are a type of fungi which are harmful to certain other fungi, including damaging fungi that cause disease. For this reason, Trichoderma’s should be used as an organic soil treatment.

They are especially useful after sowing or planting because they can consume the harmful fungi before they cause disease. BioTabs BACTREX contains 8 different soil bacteria, Trichoderma genus mould and Humic acid and soil microbes.

BioTabs BACTREX is a living product, once dissolved in water, the solution needs to be applied within 6 hours. Do not overuse.

Orgatrex is an organic liquid fertiliser. The NPK ratio is 5:1:5 and it accelerates growth and bloom. Orgatrex is made from alfalfa meal, mixed molasses, vinasse, silicon oxide and rock dust (no animal products). It contains balanced amounts of Zn, Cu, Mn, Co, Mo, S, Na, B and Fe.

When used with beneficial soil bacteria (Bactrex) and mycorrhizal fungi products such as Mycotrex the organic nutrition is slowly released during veg growth or during bloom.

Orgatrex should be shaken well before use to re-distribute any solids. Once mixed, an Oragtrex/water solution should be kept for no longer than 2 days before use.

BioTabs supplements to consider for cannabis

Although not strictly necessary, BioTabs have expanded their product range for the organic cannabis grower who wants some additional options.

Boom Boom Spray is a foliar feed liquid solution with 100% organic, vegan, natural amino acids, peptides, glucosides & minerals. It gives a nitrogen boost to produce dark green leaves and can be especially useful in vegetative growth.

5mls is diluted in 1 litre of water and sprayed onto your plants. When using indoors, spray the plants until they are dripping wet. Ideally, do this just after the lights go on.

For outdoor use, spray the plants early in the morning.

Mother plants. Spray 2 days before you take cuttings.
Cuttings. Spray two days after they are rooted.
Changing pots. Spray the plants immediately after they are transplanted.
Production plants. Spray the plants once during the growth period and if necessary, during week 1 & week 2 of bloom.
Stressed plants. Spray plants once and if necessary, repeat once more after 5 days.

Boom Boom Spray is effective after 2 hours. Once a solution has been prepared, use within 6 hours. It contains 45% Organic Matter, 5% Organic Nitrogen (N), 30% Soluble Peptides & Plant Amino Acids and 10% Glucides.

As the name indicates, the PK Booster Compost Tea gives your plants a PK boost in bloom. It contains a blend of concentrated organic compost including the following:

Bat Guano
Kelp
Phosphorus releasing bacteria
Potassium mobilising bacteria
Selected special ingredients

Not necessarily recommended as an essential additive for the less experienced BioTabs grower, PK boost has a direct impact on your plants and their yield and should not be over-used.

Bio PK 8-5 is a liquid bloom accelerator. It improves rooting, growth and flowering with the following ingredients:

Top-Booster
NPK, 2-5-8
Nitrogen N, 2%
Phosphorus Oxide (P2O5), 5%
Potassium Oxide (K2O), 8%
Comes in 500, 1000 & 5000ml sizes

Bio PK 8-5 contains seaweed extracts, vitamins, auxins and other phyto (plant) hormones. From the second week of bloom until the week before harvest, with every watering, add 1-3 ml of BIO PK5-8 per litre of water. Or, during bloom weeks 3, 4, 5 & 6, feed 10 ml of Bio PK 5-8 to each plant, diluted in at least 1 litre of water.

Guerilla Juice is a liquid fertiliser with an NPK ratio of 5-1-5. Guerrilla Juice works in conjunction with the beneficial soil bacteria and mycorrhizae fungi. It contains balanced quantities of Zn, Cu, Ca, Mn, Mg, S, Si and Fe. The blend of cannabis micronutrients ensures healthy plant growth.

It is made from alfalfa meal, mixed molasses, kali vinasse, silicon oxide and fine rock particles. To use, dilute 10 ml Guerrilla Juice in 1 litre of water. Water the plants with this solution in week 4 and then once a week.

Best cannabis plants grown with BioTabs

The Ultimate feminised cannabis seeds grow report Antonio Fernando SCROG LED SANlight

The two most common errors seen with cannabis cultivation, especially by less experienced growers are over watering and over/under feeding their plants. Both result in sub-optimised growth and harvests. Many love growing their preferred cannabis strains at home but find the process is made unnecessarily complicated by the narrow working margins offered by traditional mineral nutrients.

If that sounds familiar then it could be time to consider a much easier, and similarly priced, alternative to mineral nutrients – BioTabs. Numerous growers have taken their home-grown results to the next level simply by swapping their traditional mineral nutrients for BioTabs.

BioTabs keep your cannabis plants in the nutrient sweet spot allowing you to reach the full genetic potential of your cannabis seeds. That means yields and quality levels right where they should be – maximised. The following grow review of The Ultimate (one of Dutch Passions highest yielding photoperiod feminised seeds) gave a 600g dry yield from 5 plants grown under a total of 420W of SANlight LED using BioTabs. Check it out to see the incredible results on offer with BioTabs slow-release organic nutrients.

BioTabs nutrients FAQ

No. That’s one of the simplicity benefits of using BioTabs, they make cannabis growing child’s play. When growing in soil, the soil acts as a natural pH buffer. BioTabs are most appreciated by growers that have had a hard time using mineral nutrients. If you have experienced headaches with brown leaf tips from over feeding and reduced harvests from under-feeding, then the transition to BioTabs really can be a complete game changer. Grow in a large, aerated container of soil and just by using the basic BioTabs range you will be able to grow from cannabis seed to harvest adding with the minimum of effort.

It doesn’t really matter. No need to worry about hard water vs soft water, de-ionised water vs tap water etc. BioTabs remove the complexity from plant nutrition and allow you to enjoy the grow without needing to be a nutrient expert.

Many use a light soil, knowing that the BioTabs system will fully load the soil with a steady flow of nutrients. You can use a simple, inexpensive supermarket soil if you wish. A Light-mix soil (or Lightmix / Coco blend) from any brand works well too. BioTabs particularly recommend the following aerated substrate mixes:

50% soil, 50% clay pebbles
50% coco, 50% clay pebbles
50% coco, 50% perlite
50% soil, 50% perlite

Yes. Because soil health is improved the soil can be reused several times. If you’re growing in large containers of soil (e.g. 30-50 litres+) this offers useful cost savings.

1 Comment. Leave new

Maja Ban
31/01/2025 13:23

Good afternoon,
I have a question for you. I am groving under Led lights 3,2 micromoles, and it’s my first time using Biotabs. I want to know which soil will sute me better, Klassman Podgrond H or Atami Bigrow Mix and also, I am considering Co2 enrichment with Co2 tank. Does this require any changes in feeding scedule?
Thank You

Reply