Gravity fed drip irrigation, semi-automated: Difference between revisions

Gravity fed drip irrigation, with the intent of complete, hands free automation

Intro

Welcome to my garden! What began as an experiment, has turned into a working garden which can run alone for several weeks at a time. The garden presented is small scale, approx. 30 plants, but can easily be expanded simply by adding more branches from the above ground tank and filling it more often. It's main purpose was to eliminate the carrying of water, eliminate guess work and wasted water, while ensuring that the harvest is never at risk due to lack of water. The main benefit was that the automation worked so well that a 2 week vacation could be taken in the middle of the season. Only 3 things limit its effectiveness; drought, pump outage and overly dirty water.

Our greenhouse 20 Square meters, 4 x 5

I've run this garden with approximately 30 plants for 2 seasons. The 1st ran without filter and the daily battle with dirty droppers convinced me that a filter was needed. I created one out of sand and gravel, which made an incredible difference. This year I intend to improve the filter somewhat, otherwise won't make any changes from last year, other than exchanging dirt and changing plant location.

Description of set up

Rain water is collected underground. A pump attached to a timer runs at a specified time each day to fill an above ground tank. The fill level is measured using a standard toilet floater to shut off the pump when the tank is full.

The water in the tank is fed from the bottom of this tank, through a sand + gravel filter to remove fine contamination. The filtered water runs through 1/2" tubing and a branch of 3/16" tubing with an adjustable dripper at the end runs to each plant.

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  Intitial coarse filter

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  Above ground tank + filter

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  The drippers I used

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  April, shortly after planting

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  My tomatoes on 5 Sept.

Drippers running, one slow, so it gets cleaned: Media:Drippers_with_cleaning.ogg

The drippers are adjusted to provide approx 100ml of water per hour when the tank is full and will gradually decrease during the day as the tank empties. I estimate that each plant receives 2l water over a 24 hour period. At this time the tank is refilled, bringing the drip speed back to 100ml per hour. With time, dirt and/or algae collect on the dripper, decreasing output and must be cleaned away. I used an old toothbrush and opened the dripper to full open to flush dirt out of the tubing and dripper.

Drip adjustment

To begin the season, a glass was placed under a dripper and left to run for 1 hour and adjusted until 100ml dripped per hour. All plants were set to the same drip rate and allowed to run. During the summer we experimented with more or less water per plant and although we found it difficult to always have the same drop rates, no plant showed too much or too little water symptoms, but no records were kept since it was mainly to ensure that the system would work as expected.

Plants:

16 Tomato 10 Paprika Various others including Eggplant, Cucumber, Green Beans, salad, herbs and spices.

Lessons learned - year 1 > 2

Without the filter, the drippers required cleaning every 2-3 days, eliminating all time savings. Additionally, a dry spell left the underground tank empty, so that tap water had to be used. This may be the cause of the filter becoming dirty, allowing more dirt to the drippers. This is only suspected at this time, more testing is required to be certain.

Future Plans, full automation - here's where I want your help. Please fill my blanks!

• Automation, done dirt cheap
• Computer control (Raspberry Pi, etc) - database, programs, interfacing
• Remote control through app
• Drip adjustment with step motor or maybe something else?
• Sensor to count drops - to PC which controls drip rate
• Sensors for temp, humidity, water penetration, acidity...
• Door/window openers, tank fill measurement and pump start/stop
• Pump improvement - manual or wind/solar powered
• Electricity - it needs to be cheap, wind or solar?
• 3D print all tubing connectors and other parts
• Recycle plastic into filament (extrusion) and parts
• Walipini
• Please feel free to link your genius into ours ;-)

• Keep it simple, a child should use it!

External links

• [Garden.svg]

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Agrigulture: Irrigation: