Re: Hydroponics Organically

**K* M* <k*@iol.ie>**

There is quite a good article here Doreen

http://www.motherearthnews.com/Organic-Gardening/1977-03-01/Organic- 
Hydroponics

However,

although there are a considerable number of people practising what  
they refer to as organic hydroponics and indeed it may even be  
possible to get organic certification for a system like this in at  
least one US state such a system is not recognised as organic  
anywhere else in the world where organic growing is defined as a  
"soil based system". The Mother Earth article referred to containers  
of a soil based mixture being used for comparison in the Canadian  
trials but once again container growing is not recognised as being  
organic whether or not the containers are filled with such a mixture.  
The only situation is which most of the world will recognise a  
containerised plant as organic is where that container is the small  
one used to grow on the plant before it goes into the ground.

Organic  growing is based not just on staying chemical free but on  
the complex interraction of plant, microherd, and soil in which the  
microherd and plant between them are free to mine the soil to match  
the plant's needs. A couple of years ago I did a tiny experiment  
using four tomato plants of the same variety taken from the same  
sowing and apparently at the same stage of growth. One I planted in a  
small greenhouse soilless bed using ring culture and fed with an  
"organic" purchased liquid feed based on kelp (the only sort  
available here - you can't get fish emulsion unless you make your own  
- a smelly process). One went into the ground in an organic  
polytunnel, one into the ground against a south facing wall in the  
organic garden where the greenhouse and polytunnel stand and one in a  
sheltered spot in the field over the garden wall which does not have  
organic certification but is fertilised with composted cow manure.  
The walled garden and polytunnel are fertilised with home made garden  
compost and fertilised cow manure from the same source. I got some  
testing done on the first truss from each plant. Obviously the  
outdoor plants produced their fruit somewhat later - this is, after  
all, Ireland where outdoor tomatoes are at something of a climate  
disadvantage, but I thought the same trust should be pretty much  
comparable

The reason I was doing the experiment was that I wanted to look, in a  
small way and for my own interest, at the long term impact of the  
organic management of soil and plants in a containerised situation -  
I wanted to see whether polytunnels and walled gardens are in fact  
simply big containers and there is a long term depletion of trace  
elements in a contained system even where most of the minerals taken  
up by the plants are returned to the soil in the form of compost.

I also had a few (around half a dozen) people eat the tomatoes and  
blind mark them for flavour.

Unsurprisingly the ring culture plant showed a very different trace  
element profile - it had quite high levels of trace elements and  
sugars but they were different trace elements. The other three showed  
quite similar proflles but the field grown fruits had the broadest  
spectrum of trace elements, with the polytunnel and walled garden  
following in that order. I had expected the last two to be the other  
way around but on consideration I believe that down the years the  
polytunnel has received a lot a comfrey/nettle compost and liquid  
feed so we may have the mineral mining abilities of comfrey to thank  
for that outcome.

The tasters went for garden, greenhouse, polytunnel and feed in that  
order but there weren 't enough of them to be statistically  
significant - let's face it, there wasn't enough of anything to be  
statistically significant.

I added rock dust to the garden and tunnel - the garden has been in  
existence for at least 250 years and quite likely 2000 so there's  
been a fair amount of nutrients removed in that time and not all  
replaced.

But my point is that chemical free hydroponics is not the same as  
organic and doesn't have quite the same outcomes. That said, I'd  
rather eat hydroponic food based on fish and kelp than hydroponic  
food based on a simple NPK fertiliser.

Enjoy your tower and let us know how it goes Doreen - the fish  
emulsion dilution is in the Mother Earth article

kathryn

On 18 May 2008, at 03:12, Doreen Howard wrote:

> I received a nice surprise this morning.  My neighbor gave me and  
> installed a hydroponic growing stack.  His company manufactures the  
> growing trays, and he had a number of units for his garden and  
> shared.  I had him put it in a small perennial garden that grows  
> under my kitchen window.  I plan to plant the stack with 16  
> strawberry plants.
>
> I know Tom Alexander is on this list and a number of you have  
> hydroponic experience.  I know nothing.  But, I want to do this  
> organically, as all my gardening is organic.  My neighbor told me  
> that I have to water the stack with three quarts of diluted  
> fertilizer twice a day.  He uses the blue stuff.  I won't!
>
> What can I use that is organic?  Do you think fish meal emulsion  
> has enough nutrients for a system that will be leached out twice a  
> day?
>
> Any and all advice is appreciated.
> Doreen Howard
>
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