More Efficient Alternate Irrigation Systems

Buried Clay Pot Irrigation

• One of the most studied, and very effective systems uses a buried clay pot full of water to irrigate plants
• The capillary flow of water through the clay walls of the pot is regulated by demand - so little water is wasted
• Highly recommended! For restoration, gardens, landscaping, farming
• Clay pots worked well even in the lowest, hottest desert
• Excellent for seedlings or for starting seeds or cuttings
• Pot rim painted white to reduce evaporation

Getting Started

• Regular red clay pots work well
• Seal the bottom hole with a cork or sealant
• Use a lid with a small hole drilled in it to capture rainwater
• Set the pot in the soil so the rim is above ground
• You don’t want the dirt and leaves to wash in
• Firm the soil around the pot -- and plant

A Long Tradition

• A Chinese agricultural text describes the use of buried clay pot irrigation in China more than 2,000 years ago
• Excerpts from this book provided my inspiration -- writing does speak across time
• I later found work and use of clay pots in Iran, Pakistan, Mexico and other countries

Fewer Weeds

• Another great advantage of buried clay pots (and other deep watering systems) is reduced weed growth
• In one study weeds were cut 87%
• Less work - and less wasted water!

• Buried clay pots have also proved to be very effective when saline water must be used - or when salt is a

problem in the soil

• The steady moisture reduces salt buildup in the root zone and damage

Starting Cuttings

• Double clay pots are ideal for starting cuttings
• The inner pot is sealed and filled with water
• The moisture is maintained in the soil at an ideal level
• BCP are good for starting cuttings in the field as well

Deep Pipe Irrigation

• This method of irrigation was suggested by a traditional system from India - where water was placed in the hollow stem of a dead plant to water deeper in the soil
• Subsequent research found one study and one report from India
• This has been our best system for restoration work -- cheap, durable and very effective

Deep pipe installation

• The pipe may be about 14-16” long, 2” diameter, set vertically
• Small holes are drilled on the plant side below soil level
• A screen lid is glued on to protect wildlife

Deep pipe drip

• Where a drip system can be set up it can also be used in a deep pipe
• Smaller pipes can be used with the emitter inserted in the pipe

No waste

• Little water evaporates because the water is placed in the deep soil
• Little time is wasted because it is fast and easy to fill the pipe
• It works very well on slopes
• It develops large root systems

Excellent Results

• Survival can be good with very little water
• Mesquite trees were started with a total of only 5 gallons of water in the first year
• Not five gallons a week or two gallons an hour

Wick Irrigation

• Wick systems were also described in reports from India
• Wicks were traditionally combined with clay pots to water orchard trees
• After trying several types of wick systems I think this may be the next great thing!

Wick options

• Wicks can be used in a capillary form, where water is wicked from a reservoir to the plant through a raised section by capillary forces (as little as 20 ml day)
• Or in a gravity feed form, with the reservoir above the wick (a hose clamp can be used to adjust the flow rate)
• Wick with clay pot
• With a riser tube in bottom hole
• Capillary wick from buried bottle in plastic tube

More wick options

• Half inch diameter gravity wick with large reservoir
• Installed with treeshelter and wire cages for jack rabbit protection
• Seedlings topped treeshelter at 3 weeks!

Wick Material

• The best material has been old, used woven nylon rope (1/4”-1/2”)
• Fresh woven nylon rope can be used if it is washed with detergent to remove oils - but it is not as good as old rope
• Cotton is used in India, but tended to mold in my early tests

Porous Hose

• This system uses a vertically placed leaky or porous hose section
• It performs a bit like a clay pot--only it is cheaper and smaller
• These hoses are made of recycled rubber and hold up well
• This can be fed by a bottle
• Or attached to a drip type line
• Both have worked reasonably well
• A fast rate hose is needed to work at low pressure

Tree shelter

• Watering into a tree shelter is also effective if the base is sealed into the soil
• This can be done by hand from a hose, water jugs or using a drip type system

Perforated Pipe

• Sub-irrigation can also be done with slotted drain pipe
• The pipe is laid deep in the soil and filled with water using a water truck
• Best for lines of plants - good for landscaping

Porous Capsules

• A modern adaptation of buried clay pot irrigation was developed in Brazil
• The clay is formed into a capsule that can be placed on a water line
• These worked well -- but were more costly to make

Types

• Porous capsule made by gluing two red clay pots together (I would use Gorilla glue now)
• Porous capsules made by a staffer using a beer bottle for a mold

• These are easy to plumb in a system
• Or they can be gravity fed from a bottle or tank
• These are very efficient
• A range of smaller porous irrigation systems are sold for container plants

Microcatchments

• A microcatchment is a specially contoured area with slopes and berms designed to increase runoff and concentrate it
• Rain falling on the catchment area drains into a planting basin where it infiltrates and is effectively "stored" in the soil profile
• Used for millennia - very effective if it rains! But can be easily filled from a water truck if it doesn’t
• Microcatchments can be shaped to look more natural, but do entail disturbing the soil surface
• More appropriate in agriculture - but has worked well on restoration projects.