“Seeds for the future”
Second Chance School of Corfu
Differences between traditional and hydroponic cultivation
Controlled cultivation, instead of soil other
materials are used, roots grow in water in which
suitable nutrients are added
A lot of water is absorbed by the soil
Water can be recycled
We can avoid the use of power
Power is necessary
Great need for pesticides and fertilizers
Fewer pesticides and fertilizers needed
Low investment cost
High investment cost
Ecological, cheap but ... hardly known
o Modern and ecological
o Amazing improvement of product quality!
o Impressively lower costs!
o Internationally gaining ground against
o In Greece, however, it can hardly reach 7% of
The importance of..... the recipe
o Technology aims at creating the suitable nutrition recipe.
o Mr. Lazanakis says:
o «In hydroponics everything is ideal. A possible mistake
though, could be fatal. If something is added wrong, the
plant gets destroyed and we could lose the whole
o «My experience is talking. The first year my production
reached 40 tons, the second it reached 180!Did I do
something wrong at the beginning? Obviously! But we learn
from our mistakes»
o «Without good water quality you can't irrigate your plants»
[...] «After 4-5 heavy rainfalls I collect 2.000 cubic metres in a
tank and from there I channel water to the greenhouse.»
«Hydroponics with a substrate or plain water?»
Plain water hydroponics uses either a wet membrane
which irrigates the plant's roots or a small pond (tank)
where plants float.
Substrates, which come in various kinds, are safer.
contentious issue: should an industrial material be used (e.g
rockwool) or natural ones like pearlite and pumice?
o A hydrofertilizing machine is connected with fertilizer
tanks. An expert, using his computer, programmes the
suitable nutrition recipe: He calculates the correct for
each plant proportions of ions (nitrogen, potassium
e.t.c) according to the plant's needs and development
o A close hydroponic system demands water of good
quality. Salty water doesn't allow its circulation, still it
is less harmful in hydroponics than in traditional soil
o A fully equipped, ecological,hydroponic
cultivation is going to cost:
o About 200.000 euros / 1000 square metre. This
cost could be reduced by 50% with a few
o A plot of at least 6-8.000 square metres is
considered necessary for an economically viable
o From water:
o Soil cultivation:
60 litres/kg of tomato plant
o Typical greenhouse (with soil):
25-30 litres/kg of tomato plant
o Open hydroponic system (without water recycling):
20 litres/kg of tomato plant
o Closed hydroponic system (with water recycling):
15 litres/kg of tomato plant
o From fertilizers:
o Reduction by 50%
Hydroponics in simple words
Imagine hydroponics like a sponge:
o The roots are in the sponge instead of the soil
o Through a scientifically elaborated and highly
advanced system we can feed the plant with what we
o Nothing we cannot control reaches the plant's roots
o The plants are developing hybrids
Advantages and difficulties
1. The vegetables' taste and appearance depend on the ingredients they
2. Their quality can be planned
3. In Greece they have a great advantage: the sun
4. In northern countries the electricity cost is doubled
5. The area where vegetables grow is sterilised and workers wear
6. A lot of attention should be given to microbs and microorganisms: e.g
if someone enters a hydroponic greenhouse with a ladybird on him, as
there are no natural enemies for the ladybird, it will multiply very
Is hydroponics an organic
Hydroponics is NOT an
method, in any country of
because the plants are fed
with chemical fertilizers
that are added in water.
The body consists of
channels, special little
pots, a supporting base
and a water tank.
solutions are added
in the water tank
to feed the plants.
3.Ph measurer and
The plants need
water with a ph
of about 5.5 to
An air pump will
provide water with
clean air and all the
5. Water pump.
It will send water
from the tank to the
6.Pumice gravel or
They are light and
and support plants
in the pots.
measurer (tds, ppm,
This instrument is
very important as it
measures salts in
water, thus we can
of nutrients to be
The success key in
hydroponics is: a lot
of attention to the
last detail. The more
everything in the
better the results.
We must ensure
that air circulates
among the plants in
We need it to
should be 21-24
11. Young plants.
Plants should have
roots, free of soil or
any other dirt that
could possibly block
the water pump.
Home hydroponic garden
Tools and materials
1. Black, plastic bags (thick and resistant)
2. A styrofoam box with a lid (the one we usually
use as an ice bucket)
3. 6 styrofoam cups
4. 27 litres of distilled water
5. A marker
6. A cutter
8. Some moss
9. Lettuce seedlings or seeds, enough for 6
10. Nutritional mixture
Dr Gene Giacomelli, http://ag.arizona.edu/pls/faculty/giacomelli.htm
Home hydroponic garden
How to make it
Dress the inner part of the
styrofoam box with the plastic
bags and add the distilled water.
Put the box lid upside down on the
box and then put the cups in the
Using the styrofoam cups as a
pattern, draw 6 circles on the lid of
the box. Cut the circles into holes,
trying to make the holes about 1/2
cm smaller than your drawing.
Water the plants daily with the
mixture and make sure the water
level has not risen. There must be a
distance of 2,5 cm between the
water level and bottom of cups.
After about a week or 10 days, the
roots will start getting into the box.
As the plants grow you can cut as
many leaves as you want, without...
Make small holes at the bottom of
the styrofoam cups. Put the moss
at the bottom and then fill them
with the pearlite.
Put the lettuce seedlings in the pearlite
and add as much pearlite as
necessary around the plant.
Vertical hydroponic system
A vertical home hydroponic system can fit in
a space 1x2 m and can feed a family
throughout a year.
PVC or ADS pipes 4,5 – 6 metres long and a
diameter of 10 cm (4 inches)
2 rolls of duct tape
A water pump, the size depends on the
water flow demanded but an aquarium
pump will do.
4 corner pipes of a diameter of 10 cm (4
An air pump (optional). The system will take
air in even without the air pump but it
will function beter with one.
4 “ T” connectors 10 cm in diameter (4
Construction time: about 2 hours
2 barrels that can take 190 litres
Pex pipes or aquarium pipes 4,5 – 6 metres
Straps from hard cloth e.g burlap or cable
connectors or any other kind of
Plants and fish recommended:
Leafy vegetables, tomatoes, herbs are
suitable for such kinds of construction.
Tilapias and trout are favoured by a
hydroponic environment, grow fast and
are very tasty.
The research was carried out by
the following participants in “Seeds for the Future” project
o Andriana Koskina
o Mariliza Kolovou
o Anastasia Revythi
o Giorgos Hondrogiannis
o Lazos Tsiatis
o Agelos Yiagas
o Panagiotis Glinias