Pitcher irrigation: a water saving technique
By Altaf Ali Siyal
Buried clay pot
irrigation (pitcher irrigation) has been used to grow a wide
range of annual and perennial plants in China, Pakistan,
India, Iran, Mexico, and Brazil. In fact, it is even recorded
in Chinese texts dating back more than 2000 years.
In its simplest form, pitcher irrigation entails burying an
unglazed, porous clay pot next to a seedling. Water poured
into pot seeps slowly into the soil, feeding the seedling's
roots with a steady supply of moisture.
Pitcher irrigation uses water more efficiently than other
systems since it delivers water directly to plant root zones,
instead of to broader areas of the field.
When a pot, filled with water and covered by a lid (wooden or
clay), is buried in the soil, the water oozes out of the clay
pot due to hydraulic head difference (moisture content
difference) between the pot surface and the surrounding soil
until it is in equilibrium with the surrounding area.
The rate of seepage of water from pitcher will depend on the
type of plant and soil and climatic conditions around the pot.
The movement of water is as a result of the uptake by the
crops and it continues as long as the plants take it up and it
When the surrounding area become saturated with water and the
pot is emptied, water will tend to move back to fill up the
pot. The system is therefore self-regulating.
The surrounding soil is almost always at field capacity
(approximately 80 per cent of soil pores filled with water) as
long as the pot is not allowed to dry up completely due to
With this irrigation, deep percolation losses are negligible
since water is released from smaller areas, and the rate of
water loss can be controlled site to site by the amount of
water put in each pitcher.
Water requirements in a pitcher irrigated field can be even
less than those of a drip irrigated system (of the same scale)
due to the very low permeability of the pitchers, as well as
reduced evaporation losses.
The number of pitchers needed per hectare varies with the type
of crop. A creeping crop such as bitter gourd requires
2,000-2500 pitchers per hectare. Upright crops, or crops
producing a canopy around the pot require more pots, up to
4,000-5000 pots per hectare. Pitchers used for this purpose
should have good seepage ability (minimum 15 per cent in 24
hours) in an open air. It was found that six to twelve liter
pots are sufficient to grow most vegetable crops.
Ideal for sandy to loamy soil with good porosity (40-60 per
cent) and for small farmers, its cost is not more than Rs4500
per acre, which is about 82 per cent cheaper than the 'drop'
and the 'sprinkler' irrigation method. Pitcher irrigation is
used for small-scale irrigation where:
* water is either scarce or very expensive.
* fields are difficult to level such as under uneven terrain.
* in remote areas where vegetables are expensive and hard to
One of the advantages of using pitchers for irrigation is the
result of their water saving capacity. To compare pitcher
irrigation to flood or sprinkler irrigation one must correct
for the fact that the scales are radically different. Pitcher
irrigation is used for small-scale, while flood and sprinkler
systems are for more extensive irrigation.
Taking this into account, pitcher irrigation is still more
efficient. The 'pitcher' system saves water up to 98 per cent
as compared to flood basin irrigation system.
A farmer can cultivate about 5 acres through pitcher
irrigation on hand-pump, pond, or any simple source of water.
This method is also efficient in terms of crop production per
unit application of water.
The corn grown in Mexico on pitcher irrigation showed that the
crop production was much higher than that with conventional
irrigation methods. Pitcher irrigation is useful for
vegetables, gardening, landscaping, and growing plants in
containers - on patios or porches, where the clay pot is
buried in the planter box. It is also excellent for rooting
At least four plants of most vegetable crops could be grown
around one pot. Limiting water delivery to the area where the
crop is grown dramatically reduces weed growth - a major
constraint on production in many areas of the world. The pots
also may be refilled every few days instead of requiring
Method Productivity in kg per plant of corn Per cubic meter of
closed furrow (basin)
porous capsule (pressure)
porous capsule (no pressure)
buried clay pot
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