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Sal

Me and mindhunter have been chatting about using biobizz products in hydro ( calm down vlad ) and he pointed me to this article which i found most intresting and a bit contravesial i would like to here some fews on it from seasoned orgainc growers here,s the article


Organic Hydroponics

By Mike Nichols and Kim Atkins

Abstract

At first sight “organic hydroponics” appears to be an oxymoron.

There is considerable interest by consumers world-wide to purchase organic vegetables, but a considerable antagonism by organic producer councils to accept that it is possible to use hydroponic systems and still conform with the organic philosophies.

In fact by using nutrient solutions derived from acceptable organic sources, and using biological pathogen control measures, and recirculating hydroponic systems, a more sustainable system of crop production is possible than when using “classical” soil based organic systems.

Studies at Massey University have shown that it is possible to produce lettuce using NFT with an organically derived nutrient solution, although growth is slower than when using a conventional inorganic hydroponic solution.

The results of our work will be presented, along with a critique of the current New Zealand and Australian organic standards, which permit aquaculture, but disallow hydroponic produce from being labelled organic!

Introduction

Soil is not a good medium in which to grow plants. Most controlled environment agriculture (greenhouse) crop producers have been well aware of this for many years, and this has lead to the development of a range of different hydroponic and soilless culture systems of crop production.

In recent years there has been an increased consumer interest in the production of crops using “organic” methods. For example in New Zealand the Organic Products Exporters of New Zealand (OPENZ) survey showed that New Zealand certified organic exports in 1999-2000, increase by 100% compared to 1998-99 to over $US 30 million, and in the next 4-years are expected to exceed $US 200 million.

There is an increasing interest by consumers for organically produced greenhouse vegetables, but modern greenhouse vegetable production has moved away from using soil to using media such as peat, pumice or rockwool, or even to using medium free systems such as the nutrient film technique (NFT) or aeroponics.

The concept of “organic hydroponics” is to some extent an oxymoron, as theoretically it should not be acceptable to produce organic produce without soil, as a living dynamic soil is considered to be the corner stone for organic production. However two of the major objections by organic supporters to conventional horticulture are the use of artificial pesticides and the use of artificial fertilizer.

Both of these objections can be overcome, by using biological control for pathogen control, and by deriving the nutrient solution from organic animal and plant material.

This thus poses the question of why do organic producers emphasise the importance of soil in the system??

In fact plants do not “grow” in the soil. The roots are found in the pore space between the soil particles. So what magic property does the soil have over an artificial medium?

I suspect that the answer is that the soil is filled with a mass of living organisms, and that these micro-organisms provide a very valuable balance with nature. In this respect I can see little if any difference between the modern practise in hydroponics (where the solutions are re-circulated through a deep sand filter) and growing in the soil.

Hydroponics is NOT a sterile system. In fact it is impossible to keep the system sterile, so the modern approach is to try to control soil borne pathogens by biological means. As the plant roots do not grow in the soil, but in the pore spaces between the soil particles, it is really not important whether the soil particles exist or not except to support the plant.

Public perception

In a survey carried out in New Zealand recently on behalf of NZ Vegetable Growers Federation by Colmar Brunton it was found that in a survey of people who purchase organic vegetables just under 40% purchased them because they had no (or less) sprays applied. Nobody referred to the fact that they were grown without the use of artificial fertilizer. There is a huge consumer misconception regarding spraying. I must add that NZ VegFed are not antagonistic to organics, in fact they see it as a potentially valuable niche market.

In fact the whole organic movement is founded on the premise that:

Healthy soil—healthy plants—healthy people.

Unfortunately none of the links has ever been “scientifically proven,” so the concept that because plants are grown in a healthy soil does not mean that they are axiomatically resistant to pest and diseases, and (to date) nobody has been able to demonstrate any major difference between organic and conventionally produced crops from a human health viewpoint.

Certainly in the realm of pesticide applications the organic people have not been perfect. Copper sprays until recently were acceptable in organic culture, and in recent time have been implicated as a potentially dangerous heavy metal, while rotenone (derris) is now regarded as a risky chemical. Even BT is under fire in Auckland, where it is being used to control the painted apple moth.

One of the major claims of organic growers is the reduce leaching of nutrients through the soil. Recirculating hydroponic systems (with no leaching) are clearly much more efficient from this point of view!!!

The Soil

One of my pleasures as a University teacher has been to observe students shock when I tell them that “soil is not an ideal medium in which to grow plants.” Many have always considered soil as the only possible medium, and it takes some discussion to explain that although soil has some admirable properties, not the least being it’s ready availability and its ability to provide excellent water and nutrient buffering, it is not ideal, because it is impossible to provide optimum levels of water and aeration at the same time. It is mainly for this reason that high value (mainly greenhouse) crops tend to be grown hydroponically in “artificial media”.

The emphasis by organic producers that the soil is an essential component for organic production needs to be questioned. Plant roots grow in the spaces between the soil particles, which are inert. By using a recirculating hydroponic system soil micro-oganisms will become established in the media, or where no media is being used (NFT, aeroponics) the solution can be cycled through a slow sand filter, which will essentially have the same effect. It is difficult to see how this differs essentially from a “soil grown” production system.

Pest and disease control

There is unlikely to be any huge difference in the control of pests and diseases in a conventional or in an organic greenhouse production system. Few greenhouse growers use pesticides these days, as they rely very much on the control of the plant environment to reduce fungal diseases to a minimum (by reducing humidity), and various biological agents, such as Encarsia formosa to control pathogens such as white fly. Conventional growers dislike using pesticides just as much as organic producers. In fact as most conventional growers use bumble bees for pollination of tomatoes, the use of most (if not all) pesticides is extremely counterproductive.

Grafting onto resistant root stocks is always an option for greenhouse tomato or cucumber growers IF soil borne pathogens are a problem.

Nutrient and water delivery

Hydroponics involves a range of different systems to deliver water and nutrients to the roots. From media based systems using peat, sawdust, bark, pumice, perlite, or rockwool, to systems without any media such as the Nutrient film Technique (NFT) , deep flow or aeroponics.

One of the key factors of most (if not all of these systems) is that it is possible to use a recirculating system, in which the “drainage” solution is collected, and further nutrients and water added, and then returned to the plants roots. Such a system is extremely nutrient efficient, and is therefore currently the most sustainable and environmentally friendly use of nutrients that exists. In the field there are very real problems in some countries from the excessive use of organic matter in the soil, leading to a build up of nutrients in subterranean water. Pig manure has been a major environmental problem in the Netherlands for example, and even within New Zealand a lot of the water pollution can be laid at the unsatisfactory disposal of dairy farm waste—very organic, but still a major problem!!

Nutrients

The major challenge facing the “organic hydroponic” producer is to develop a satisfactory nutrient solution. Two readily available organic products—fish meal and seaweed contain large quantities of sodium and chloride, which is not a problem in the field, as they are easily leached out by rain, but in a hydroponic system this can not be easily done. Vermicaste derived solutions have very low levels of nutrition, and probably the major source of organically derive solutions will come from animal manure (probably dairy waste). Unfortunately plant roots tend to absorb ions and not molecules, so it is essential that the nutrient solution is completely broken down (oxidized) and that will involve oxidation tanks and then holding tanks for the concentrated solution. Finally, of course, it will be necessary to monitor the nutrient solution to ensure that the nutrient levels remain in balance, and are at the optimum for good plant growth.

New Zealand Standards

Currently the Standards Association of New Zealand, and the equivalent body in Australia are developing a set of Organic Standards. In fact, the proposed New Zealand standards are very similar to the Australian ones.

Both of these standards prohibit the use of hydroponics, without providing any explanation, but permit aquaculture. I am well aware of the aquaponics research conducted at Curtin University in Perth by Marios Vasiliou, and I find it very difficult to see how such a system can not comply with any organic standards.

I must add that the committee which established the New Zealand organic standards did not include any representation from mainstream New Zealand horticulture (such as VegFed) and comprised a majority with strong “organic” affiliations.
OMH
That backs up what has been said on here before. Its possible to run a hydro system using organic nutrients as long as you keep the nutrients very well oxygenated in the tank. Having 2 or 3 airstones in a standard 80 litre tank should take care of that quite nicely I would think. A circulation pump might also be a good idea, just to stop the nutrients settling and seperating out.

I might have to give this a try, next time I do a crop. I am finding that the plants are just not fattening up the way I would expect in the pots of mud, and it would be nice to be able to run an NFT system with Biobizz, just to see how well it does
Bish
QUOTE
I am finding that the plants are just not fattening up the way I would expect in the pots of mud


They'll pack it on in the last two weeks wink.gif

It certainly would be an interesting experiment using Biobizz feeds in hydro mate wink.gif
VRG
QUOTE
Its possible to run a hydro system using organic nutrients as long as you keep the nutrients very well oxygenated in the tank. Having 2 or 3 airstones in a standard 80 litre tank should take care of that quite nicely I would think. A circulation pump might also be a good idea, just to stop the nutrients settling and seperating out.


Yeah, that's the only problem I can see! Other than, if using a Hydro dripper system, the food would clog the drippers. Could maybe work well in NFT or some sort of bubbler though.

If I were to give it a try in NFT, i'd stick two pumps in the res. One sucking from the bottom and blowing straight up at the underside of the tray (this oxygenates the solution realy well), and one on it's side moving the nutes around the tank. This should stop the nutes from seperating out.

Also, on most Organic nutrient bottle's, it says once mixed, to use straight away, I pressum this is just down to them seperating out, but could it be for other reasons??

Another thought! 34.gif
When growing in compost, your feeding your plant with the mix, up until you add your nutes. Does the bio-bizz grow food have everything necessary to work in an inert medium?? just a thought.

Good topic sal,

VRG
Arnold Layne
Hmmmm.
Sal

On the biobizz site below they say you can use the products have a look at the fag usin biobizz in hydro




Biobizz
Bish
QUOTE (Arnold Layne @ Apr 28 2004, 04:21 PM)
Hmmmm.

deep in thought mate?

lol.gif
Red Dragon
QUOTE
On the biobizz site below they say you can use the products have a look at the fag usin biobizz in hydro


Hmmmm!!
Arnold Layne
No M8,
just smokin the GD......
For me, I just don't buy the "improve on nature" philosophy.
On a ramble: I recall yonks ago when I used to Fly-fish at every given having a chat with a guy running a huge lake. He was stocking Triploid Trout and loudly declaring that they could not escape into the river system, and anyway it was "genetically impossible for them to breed". Ah, the confidence of those priests in white who worship the great god Science!
Pooh! Took the little fekkers all of a season to escape into the river system and breed both amongst themsleves and with the native wild browns.
So OK, a wild stock is a mix of sizes, conditions etc etc, and yes you can stock a pod/ lake with perfect "bred" specimens. But I know which tases better, and which is happier/healthier.
You know, I'm sure there's a conncetion the the topic here...













but what the fekk are we on about? w00t.gif
Damn! This GD's cheeky aint she?
OMH
another thing that I thought about is PH.

Soil buffers the ph of the nutrients, but you don't get that in Hydro. Living in a hard water area would mean that a shitload of ph down would be required....2 things

Adding a shitload of phosphoric acid could very well kill all the nice microorganisms that make the organic nutrients work. I know that you should not use oxyplus with organic feeds for that very reason - would be interesting to find out what ph you can take Biobizz down to before it goes tits up

The other thing is...well, once you start dumping phosphoric acid in there, its not organic anymore, and you end up will all the phosphorus build up issues surrounding Hydro.

I am guessing that you would need to use something like citric acid, and you would need quite a bit of it.

Any thoughts?
Bish
what's the normal/average ph for hydro though?





Sal


citric acid is very potent mate i use it now a tip of your finger is more than enough for 5 litres
VRG
QUOTE
what's the normal/average ph for hydro though?


You want to be aiming for somewhere around 5.8.
EnigmaticOne
well I can contribute this.....

My tap water has a PH of 8.2 rising to 8.7 after standing 24 hrs. After addinf biobizz nutes the ph came down to 6.9!!

EO
oldtimer1
Most of the arguments are totally irrelevant spin.

Organic farming is about sustainable practises, putting back what was taken out. It is all about how animal and plant waste is managed.

He is outright lying quoting untruths, distorting and misrepresenting facts.

It is true that chemical farmers slurry pit spills and spreading slurry on soil cause nearly as much pollution to water courses as the run off from chemical salt fertiliser applications. But both of these have nothing to do with organic farming whatsoever.

The problems of disposing of billions of gallons of pig slurry by factory farmers in both Holland and even worse in the USA is about cheap food and profit.

Organic farmers do not factory farm, pigs have to be raised free range with only a few allowed per acre. Where animals have to be kept in they are bedded on organically produced vegetable waste such as wheat straw. No slurry production/collection is allowed even in dairy units, all animals have to have bedding. The soiled bedding has to be fully composted so that the minerals and nutrients are locked into the humus before they are distributed back to the land. This is in harmony with the natural carbon cycle.

The mineral content of both fruit and vegetables are 15 to 75% lower today than they were 40 years ago. This is a direct result of unsustainable chemical farming practises. The carbon sink of the worlds top soil is being depleted at an ever accelerating rate the vast majority being over the last 90 odd years..

To call soil inert is not true, nearly all its constituent parts are going through constant change that supply nutrients and minerals to plants. Its a living thing with millions of living micro organisms in every teaspoon full. If cared for properly land requires virtually no input of fertilisers or minerals. If we did not pour our toilet waste into sewerage farms to separate the solids/nutrients and dump them in the sea, if we composted all our other carbon waste there would be no need for chemical fertilisers of any sort at all..

There are hundreds of elements in soil that plants take up, who knows what of them we may need. The soil has conserved and maintained these elements, minerals and nutrients for hundreds of thousands of years. Every thing you are made of has been a plant or animal hundreds or thousands of times before, except the new ones made and introduced to the food chain by the chemical industry over the last hundred years or so.

The chemical and mineral mining multinationals constantly give funds to universities to come up with this sort of crap. The supermarkets in this country have been pushing the uk organic certification bodies to accept hydro produced strawberries as organic. Its a huge no no. Organic growing takes into account the entire environmental consequences, not for a few months but continuously.
chip
QUOTE
He is outright lying quoting untruths, distorting and misrepresenting facts.


Yep, aint that the truth. You hear anti organic, scientists spouting this sort of crap all the time. You often here the misrepresentation of organic farming by scientists who do not really understand the organic philosophy or even have a rudimentary grasp of the standards. Saying that manure and slurry are big polluters is true, but its the conventional farmers who cause the trouble. It is the storage of huge quantities of shit at intensive production units that causes the trouble. It leaks into water courses and farmers spray it onto their fields causing all manner of environmental pollution. as OT has said, organic farmers compost their manure to make it a more useful product for the soil, properly recycling waste which helps to maintain the fertility of the soil. This is the big difference, organic farmers do not add the nutrients, they help the soil to build its own fertility which helps the plants to grow and that is why you cannot do organic hydroponically

The author of that report is wrong in many respects. What was/is he? An undergrad at an agricultural college, or more likely doing chemistry!

When people try to apply the same 'scientific' wisdom of conventional farming to organic they always come up with similar misinformed rubbish as this fool.

Soil is still not very well understood. The EU has recently begun a huge research project to try and find out more about it. To say it is inert 34.gif

I have spoken with some of the old school organic growers and they sometimes talk about the passage of energy. It is the passage of energy from the microbes, bacteria, insects etc in a living soil that helps organic plants to be more healthy. That is why organic food is healthier and more nutritious.

OK, NZ boy said it isnt, but a systematic review of the evidence shows that 50% of the research shows no difference but the other 50% shows that organic has higher levels of vitamins, minerals and livestock and dairy products have higher more beneficial levels of essential fatty acids!

Healthy soil is the foundation of a healthy and sustainable civilisation. If you look to the past, those civilisations that havent cared for their soil have perished. (nert! What a dumb ass!! Could go on for ages about this one!! 34.gif )

A famous writer/economist/..... E F Schumacher once wrote that if you concentrate on health, beauty and permanence, you get productivity as a bi product! (something like that anyway)

Hydroponics is about productivity.

unsure.gif why do i grow hydroponically again!!??

Sal
QUOTE
Hydroponics is about productivity.
which is important if you only have a small space. I work in a very small area unless im growing clones in sog i have to take my pot plants out of the grow area place them on a mat in the bedroom and when it comes to repotting its the same which i can tell you aint good for the carpet you would have to see how i work to understand where im comming from

organics for me is about taste and not put chems into my weed
QUOTE
why do i grow hydroponically again!!??
( Nft ) Space , humping soil up and down stairs the fact that my 250 watter just aint feeding me and my sons need. Thats why im thinking of nft and would like to use organic subbstance,s
Bish
Top posts OT & Chip thumbsup.gif

I was listening to that report on Radio 2 yesterday about mineral depletion in our soil - scary stuff.

Bollocks to intensive farming, & onwards & upwards for the organic farmers of this country - Who actually put something back!
oldtimer1
What prog was that bish. Do you know if its avalable online?????
Bish
I'll have a look mate.

Can't find anything from yesterdays show, so sadly no.

It was on the JV show.
oldtimer1
Thanks for looking Bish. I have spent about an hour looking found this its pretty interesting and relates to the whole thing big time.

Take a listen to "Transforming the Earth" if you have real player, people like this give me hope.
Bish
Can't get realplayer to work from that link mate - it's probably my end though. PC needs medical attention!
oldtimer1
Works for me but I think the beeb have an online player for PC’s

Try here "Changing places" look for:- Transforming the Earth.
Bish
Can't get realplayer to access the net - I'm not using IE anymore, so wondering whether that has summat to do with it?

edit - Yep, it's Firefox. Just tried with IE & it loads.

Cheers for that link mate smile.gif

edit again - how can i allow realplayer access to the net using Firefox? Anyone? Mickle? lol.gif
oldtimer1
Don't know PC's Bish but on a mac for any player to work in a browser you need to put a copy of the player plug in in the browsers plug in folder.

Make sense?
Bish
Ahhhh, yep, makes sense - cheers smile.gif

Got to reinstall real player for it to work, according to the Mozilla faq.
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