Colin Austin  ©  10 August 2021Creative commons this document may be reproduced but the source should be acknowledged. Information may be used for private use but commercial use requires a license.


evolution of soil and plantsThis is an update on the practical side of making and managing Gbiota beds. I assume you are familiar with the previous publications and videos available under videos, blogs and growing in the menu.

cells communicateThe major developments are the use of the compost tube to give better and faster composting and the conversion of the school bed from Wicking bed to a Gbiota bed and the use of a solar powered pump and the Gbiota lock down bed.

controls appetiteI also give an overview of the Gbiota bed principles to emphasise that Gbiota beds are about enhancing our gut biology by growing plants that are pre and pro biotics and are much more that just growing a few nice vegetables – that is the by product.

I also wrote a sister article Anthropocene which gave an over view of why we are in danger from a food crisis and need Gbiota beds.

What matters and does not matter

replace body partsPeople often send me pictures of their Gbiota beds. They vary from masterpieces which would challenge Chippendale to little more than piles of rubble but the quality of manufacture is not as important as following these basic principles.

Why Gbiota beds

immune systemIt may seem at first sight that Gbiota beds are just a neat way of growing vegetables. The real purpose of Gbiota beds is to enhance our gut biota by breeding beneficial biology in the soil. These enter the plant and then into our gut. The plants just provide a convenient way of packaging this biology and act as pre and pro biotics.

wormsThis may seem a bit pedantic but is actually important in understanding Gbiota beds.

The beneficial biology is bred in the soil and in the creatures which inhabit the soil – they have stomachs just like us and are important for breeding the beneficial biology. Worms are the most important of these creatures.

Breed the bugs

spinachManaging a Gbiota bed is like managing a dairy farm except our cows are a lot smaller – but they need the same things – a nice place to live and the right sort of food and water.

It is just a fact of life that there are good bugs and bad bugs. We have chemicals which are highly effective at killing bugs but they tend to kill all bugs so we have to use a different technique, create the conditions which favour the good bugs so they out compete the bad bugs.

800 speciesof micro biologyFor the good bugs to thrive we must feed them the food they thrive on. Fortunately they are very happy just eating clean organic waste (clean meaning free of chemical insecticides).

sunflowerBut plants capture sunlight, carbon dioxide from the air and water to make sugars which they exude from their roots to attract compatible biology. Each species of plants have their preferred biology. For example Sunflower attract the highly beneficial mycorrhizal fungi.

The good bugs and the beneficial soil creatures are very fussy about the moisture level, if it is too dry they cannot breed, if it is too wet then the bad bugs will out compete the good bugs so the moisture level is critical – what I call Goldilocks moisture – not too wet and not to dry.

That is achieved by the partial flood and drain system which is an integral part of the Gbiota system.




gbiota bed principles The diagram shows the basic layout of all types of Gbiota beds. An Ag pipe runs from the top end of the bed, down and along the base and up and over a soil dam then an exit to drain any excess water which is caught in a sump for reuse.

In earlier designs the water entered the bed through the upper end of the pipe but I have now changed over to using a compost tube.

I still keep both ends of the pipe open so it can be flushed out as according to Murphies law ‘if a pipe can get blocked it will’ so having both ends open means that it is easy to flush out with a high pressure hose.

compost tubeI now use a compost tube as an inlet, this is simply a basket or even just a hole made with an auger of a small trowel.

The water trickles down through the compost mix and fills the Ag pipe but because the pipe goes up and over the soil dam it will flood the base of the bed to the height of the soil dam when it will overflow into the sump.

On earlier design I used a pipe to drain the outlet water back into the sump but – as I found out the hard way – if this pipe is not big enough (or more likely gets blocked) the bed will flood which can drown the worms and even kill the plants.

trenchI now use a trench so I can check that the water is flowing from the outlet pipe. I am growing water cress in this trench which gets a nice flush on every irrigation.

When the water is turned off the water will leak through the leaky soil dam and back into the sump. This avoids stagnant water which will encourage the bad bugs.

This means the entire base of the bed is momentarily flooded (saturated) after which the water will wick up towards the surface.

You can adjust the water level by the height of the soil dam and can even saturate much of the bed – but my preferred method is just to wet the base of the bed so the surface is dry.

This helps stop the weeds, slugs, snails and caterpillars – which are just an inevitable part of any organic growing – but it does mean that it will be necessary to surface water during germination.

I get the soil really wet before adding the seeds, cover with Biomin then just gently sprinkle adding the minimum water to keep the seeds moist. Over watering can lead to the seeds rotting.

When the plants have developed their roots we can stop surface watering and get rid of any weeds seedling that may have germinated along with our crop.

Dense planting, as is commonly used for micro greens help manage the weeds.

Breeding layer

exuding sugarsWhen a Gbiota bed is first made there are generally three layers. They may not exist as separate for very long as the worms, which are a critical part of Gbiota beds, will move through the bed transporting nutrients around the bed. The ‘lock-down’ Gbiota bed, which is a simplified Gbiota bed to provide people living in apartments with fresh Gbiota food during may have everything premixed.

The very bottom layer is for breeding the biology and is made from a mix of organic waste, preferably chopped and if it containing roots of plants that have growth inhibitors (their natural protection against annoying neighbours) partially composted (labile or young compost).

Animal manure can be added to increase nutrient and nitrogen levels. All manures are good but chicken manure is often readily available and high in nitrogen. It is also often highly acidic so adding some balancing material like lime or dolomite may be needed.

I used to add Biomin – a rock dust with trace mineral and biology – to this layer but now add this to the surface layer when germinating.


clayThe next higher layer is the rhizosphere or root zone. This should be a nice loamy soil but it is usually a question of making do with what is available. I seemed doomed to live on clay which can be readily converted by the classic clay breakers like gypsum which actually needs biology to break down the clay.

wet clayI have found that adding cracker dust (fine rock dust used for driveways) helps in preventing that concrete like mix after clay has been wetted and dried out – cheap and adds some minerals but unfortunately unknown composition.

I used to add Biomin to this layer to provide the biology and trace minerals. This is essential but I now add this to the germination layer as it seems to give me better germination.

Germination layer

bio,The top layer is for seed germination. It is important that this is fine to give contact with the seeds. I now use Biomin for this top layer at a rate of about 3 litre per square metre. (May be just 2 litres for small seeds for sprouting). Just sprinkle the seeds on the surface then cover with the Biomin.

I used to mix the Biomin with the lower layers to provide the minerals and biology and use fine soil for germination but I have found I get better germination by using Biomin for the germination layer.


If we are using an open bed, eg the bed is in contact with a good quality parent soil you may find that the biology will just find its way into the bed without any action.

But if you are using a closed bed, or an open bed with poor parent soil, you need to make sure that the biology is introduced.


wormsWorms are essential, my experience has been that in open beds (in contact with the parent soil) they just find the food source in the Gbiota bed and breed up nicely. If you have poor parent soil or are using a closed bed then it may be essential to add the worms.

These are often available locally but worm eggs are available commercially, there are links on my sister web site for both Biomin and worm eggs.

I don’t manufacture or sell anything but I am in regular contact to ensure that the products conform to specification.

Managing Gbiota beds

What to plant

There are thousands of edible plants but we only seem to use a few on our modern food system. I am continuously experimenting with new species – often I must admit with spectacular failures.

Every plant has its own horticultural protocol (how you grow it) which may not be readily available so I just get it wrong, climate is an issue as I live in Queensland in the dry tropics with high winds and temperatures so some plants just cannot handle the conditions and even when I am successful they just don’t taste good so they end up in the compost bin.

But there are other plants which just grow and will self seed almost continuously and the leaves can be trimmed (see video on tipping).

Now bearing in mind that these are the plants that thrive on my block in my soils and climate conditions and are resistant to numerous pest we have here – these may not be applicable to your conditions here are my basics which together supply a steady stream of biology filled plants.

spinach plantTop of the must list – Spinach – preferably the climbing or Ceylonese spinach. It seems to grow better in the warmer times when it grows like a weed just out competing everything else around and seems to be resistant to insect attack (big problem for me).

alfalfaAlfalfa is another staple which grows well in the cooler winter months, it is very good for tipping but eventually the stems will become tough and the bed will meed replanting.

linseed or flaz plantAnother stable is Linseed or flax. I like this because it is high in omega 3 – it grows all year round and if you can keep up with the tipping the stem regrowth is still soft enough to eat without stripping the leaves off. If you don’t keep it trimmed back the stems get tough and it will go to seed.

Celery is another good plant which readily seeds and is almost maintenance free. My block is full of self seeded celery.

Radish is another good crop and the young leaves make a good addition to the green smoothie but they get bitter as they get older so there is a gap in production when the leaves have become bitter and the roots have formed.

I can grow leafy lettuce but they tend to go to seed very quickly in the warmer period – but they seed profusely.

I had very little luck with the staples of cauliflower and broccoli – it is just too warm and the insect love them but sprouting broccoli is a different beast altogether – it is among the fastest germinating crops, almost as good as radish and is excellent for tipping.

I can just about grow the various cabbages and kale but I find the various Chinese cabbages better suited to my climate but the insects also agree.

While many growers just grow one crop per bed I try and grow as big a combination as possible, each plant species encourages different biology and a mix is better protected from the very present insects. I am quite happy to inter sew and re-seed as I harvest the plants so there is always something growing.

Managing the moisture level

The moisture level is dominated by the height of the soil dam. As long as the pump is run long enough for the bed to be filled to the level of the soil dam the run time has little affect as the water just flows back into the sump.

The frequency of irrigation cycle does affect moisture level and the spacing between irrigation should be long enough to let the moisture level stabilise.

Lock down bed

lockdown bedThe lock down Gbiota bed, developed to help improve the immune strength of people in lock down, is purely manual.

I recommend the use of the swivel drain pipe, when it points downwards it is a Gbiota bed with external reservoir and a pulsed irrigation cycle, acceptable for people in lock down. However the swivel drain pipe can be rotated to point upwards when the bed is a classic Wicking Bed with internal storage allowing longer periods between irrigations – at the expense of less optimum conditions for the biology.


I sprinkle during germination but as soon as roots have formed I swap to the partial flood and drain system

In my set up I have a rain water tank which in the dry tropics is a bit of a joke as our rainfall in the dry is so small so I have a float valve and timer to fill the tank each morning from mains water.

This then feeds into the sump again with a float valve. I have timers which control the pumps which take the water to the beds with all excess water returning to the sump.

On the small boxes I use the pond pumps but for the in ground beds I use a submersible pump with float valve as the higher flow rate means they can empty my sump very quickly.

Even in winter, which is still quite warm and dry I will set the timer to run twice a day but I keep the run time as short as possible, which I can easily tell by watching the outlet.

I have a variety of beds which give me run times of between 2 and 5 minutes.

In our summer, which is hot with dry winds and very high evaporation I will run the pumps up to five time a day. I am sure that this would not be necessary in cooler climates.

In the summer we get the cyclones which can drop an amazing amount of water in a short time which is why all my beds are raised so the Ag pipe can drain the beds without the top layers becoming saturated.

Solar pumps

I have one bed running with a solar power pump. This is just a cheap pump intended for ponds which works quite well on a small bed. Without power to run a timer it would run for far too long so it is necessary to create some shading. I can just move the panel in winter but in the summer I have to rig up a shade.


My system is totally automatic but there is a big difference between automatic and maintenance free. The sump and the filters have to be cleaned on a regular basis, before the virus I could go away for a couple of months and it would still be running fine just a lot of weeding and cleaning when I get back.


As our friendly bugs eat the organic material the levels in the bed will drop so we need a way of continuously topping up the beds.

Simply adding more raw organic on top of the bed is not an option as this can be quite toxic to the plants and will also release carbon and nutrient to the atmosphere.

The simplest and most effective way of composting is to bury it in the ground, more of the carbon and nutrients will be retained, partners who are not quite so keen on the smells from composting will have less objection and it is not taking up any space.

The negative about digging up the beds is that this damages the soil structure particularly the mycorrhizal fungi hyphae.

These issues are resolved by the compost tube. In larger beds a basket filled with organic material is placed above the Ag pipe and the inlet pipe (typically with an elbow) located on top so the water has to soak down through the organic waste.

When the organic waste has fully decomposed the contents are emptied out on the surface as a mulch and the basket refilled. Small beds can simply have a hole made with an auger or small trowel.

Lock down Gbiota beds

gbiota lockdown partsThe whole point of Gbiota beds is to enhance our gut, which is home to much of our immune system. It seems axiomatic that in the middle of a pandemic it is better to have a strong rather than a week immune system.

To prove the benefits I would have to get a couple of thousand volunteers, feed one half Gbiota food and the other junk food, put them in a room filled with the virus then after a couple of weeks count the dead bodies. Bit short on volunteers though.

gbiota lockdown 2They are dead simple to be used by people in apartments. Just take a standard tote box, fit the internal Ag pipe with soil dam made by putting a spacer pipe under the Ag pipe.

Fill with a soil and compost mix (the local council could provide a soil mix). Make a compost hole with a small trowel and seed.

augerAfter initial seeding and watering the bed would be watered through the compost hole and the excess water caught in a bucket. (Note how brown the water is).

compot teaI am also suggesting fitting an elbow at the outlet. This would normally be pointed down so the bed fully drains but could be rotated to point upwards when the bed becomes a conventional Wicking bed so could be watered less frequently if needed.

Conversation of school bed to Gbiota bed

solar panelIn my video on the school project I made a conventional wicking bed. I decided to convert this to a Gbiota bed which I did very simply by burying a small tote box under the exit pipe and fitted this with a solar pump and float valve so it was automatic.

I used a simple solar pump designed for a normal pond. This works fine but runs for far too long so I had to locate the solar panel so it only catches the sun for a short period, in my case about an hour at midday.

Please not the name Gbiota is a registered trade mark. It can be used for non commercial use but to ensure that any food promoted as Gbiota food meets set standards anyone wishing to sell Gbiota food or manufacture Gbiota beds for sale should get prior approval.

Gbiota symbol

Forward delta

Backward anthropocene

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