1. Sand hydroponics: An alternative
technology for pre basic potato
seed production.
By Daniel G. Mbiri CIP SSA
d.mbiri@cgiar.org
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2. t
Introduction
In sub‐Saharan Africa just like the other humid tropical
areas Ralstonia solanacearum poses a serious
challenge to potato seed production.
There has been an increase in consumption of potatoes
One strategy for overcoming this challenge was to
increase area under production and yields per unit area
CIP intervened through introduction of aeroponics
technology in the year 2008 under the 3G technology
Aeroponics technology revolutionized production of pre basic
seeds in sub‐Saharan Africa

3. Aeroponics requires constant supply of electricity
In many Sub Saharan Africa countries there is
unreliable supply of electricity and man power
Sand hydroponics offers an alternative technology for
clean pre basic potato seeds production
Sand hydroponics uses ordinary sand sterilized with
ordinary sodium hypochlorite bleach
An elevated tank is used for the flow of nutrients
solution by gravity.

4. Sodium hypochlorite bleach is cheaper than
steam boilers based technology
Sand hydroponics offers an alternative
technology for clean pre basic potato seeds
production.
Materials and methods
The screen house
Sand hydroponics technology is screen house
based technology. The screen house must have
a water proof roof

5. Sketch of simple screen house Sand hydroponics unit

6. Water source
A dependable source of clean water should be convenient.
A pH meter and an electric conductivity (EC) meter can be
used for monitoring EC and pH of the water
Sand
Sand that is too fine is not convenient as it compacts and
limits root development.
Sand recycling
Sand can be recycled after one harvest. Ones through with
harvest, all organic material (roots, stems, tubers) are removed
and bleach is used just like on fresh sand.

7. Nutrient solution
Greenhouse grade fertilizers are used. The following can
constitute 1000 Liters tank:
1.potassium phosphate 136 g
2. Calcium Nitrate 236 g
3. Potassium nitrate 504 g
4. Magnesium Sulphate 100 g
5. Microsol B 12 g

8. Results and discussions (season one)
Clone Tubers per
plant
Tube per M2
381381.13 Box 6 431
Local
variety
Box 4.4 320
Local
Variety
pots 19.9 550

9. • An intermediate technology
• In Sub Saharan Africa electricity supply is still low
compared to western developed economies.
Sand hydroponics promises an intermediate
technology .
• Economically feasible
• The use of easily available timber and sand
makes sand hydroponics a technology of choice
for seed production in sub‐Saharan Africa

10. • Environmentally friendly
• Potato plants from sand hydroponics are
grown on sterile substrate and there is no
effluent discharged into the environment
• Simplicity of the technology
• Sand hydroponics is so simple that any rural
group can implement on simple wooden
boxes or pot

11. • Simplicity

12. • Costs Comparison of production costs per season
GREENHOUSE SYSTEM INITIAL COST ($) COST/SEASON ($)
Aeroponics 3,543.21 2,273.32
Sand hydroponics ‐
beds
2,768.45 1,364.44
Sand hydroponics ‐
pots
908.04 878.41
Conventional ‐beds 13,308.81 1,795.82
Conventional ‐pots 10,556.84 1,039.42

13. • Conclusions
• Sand hydroponics is the technology of choice in sub‐
Saharan Africa
• To meet the increased demand for clean seeds Sand
hydroponics is the way forward
• Sand culture is one of the most efficient and cost‐
effective methods of soilless culture
• Sand hydroponics is new in the region and there are
prospects of replicating it to many community groups
and institutions within sub‐Saharan Africa.

14. Recommendations
• Sand hydroponics technology to be replicated
in other countries
• Research works on side effects of sodium
hypochlorite to be carried out
• Research work on the number of times sand
can be recycled
• Both aeroponics sand hydroponics should be
implemented simultaneously in SSA

15. THE END