Hệ thống tưới nước tự động

OPENING PART

1. The necessity for the research to be conducted
Firstly, Vietnam’s agriculture is still out of dated with a small number of
scientific and technological researches to be applied in reality. So many cultivation
techniques and processes have been conducted based on farmers’ experiences rather
than scientific requirements. Besides techniques applied to growing and taking care
of plants, watering is one of the most important works in agriculture to make sure
that plants can grow well. Once plants are watered properly according to scientific
requirements in agriculture, it is less likely for pests to develop, therefore, it will be
unnecessary to use pesticides. Consequences, productivity will be higher and
agricultural products shall be safer.
The second reason is the fact that using watering trucks on roads in the city
center can contribute to cause traffic jams.
On the other hand, industrialization and modernization has appeared in all
aspects of Vietnam’s society so automatic equipment and machines are being
gradually used to replace human beings. Therefore, more and more watering
equipment are being researched, designed, manufactured and applied. There are
many types of watering equipment (rain ejectors, atomizers …) with many different
parameters which are suitable with many different kinds of plants. They are made in
many different countries such as Israel, Korea, Taiwan, China, etc… Consequently,
it will be very convenient for users to choose one that best suits their needs. In order
to apply them on large scale, it is necessary to select watering systems that both
meet scientific requirements and are suitable with economic and technical
conditions. Watering system must make sure that roots, leaves and atmosphere have
sufficient moisture so that plants can grow well; water-saving system shall create
conditions for plants to absorb nutrition minimizing erosion, land degradation and
environmental pollution. Automatic watering systems can be combined with

ii

fertilization and using chemicals in agriculture. Moreover, with an automatic
watering system, humans shall not have to water and supervise watering time
anymore so it helps save labor force. With this system, watering is totally
automatic. Water level shall be adjusted depending on temperature, moisture,
seasons, etc. All these conditions shall be inputted into the system then it shall
calculate and give accurate time to pump water. Laborers shall not need to care the
watering work any more. Thanks to proper watering and calculating more accurate
water level, plants shall grow better.
2. Reasons for choosing the topic
Automatic watering system (drip watering, atomizers …) is now the best
watering system to be applied widely in developed countries which can meet
scientific requirements for plants. The automatic watering system is a reasonable
form of watering that helps save labor force and cost. It has been widely used in
many countries in the world. However, only in the past few years, using this system
has been a trend in Vietnam. In the context of modernization in agriculture and
rural areas, automatic watering system has become more and more popular;
nevertheless, not all farmers are able to use it because of its high price.
On the other hand, strong development of science and technology makes life
more convenient and modern. Thanks to the development of electronic techniques,
modern devices and machines are manufactured to take over hard jobs requiring
high accuracy that were conducted by humans before. Advancements in electronic
technique have been quickly applied in many sectors: industry, transport, aviation,
etc. Automatic devices have played very important parts in constant development of
these sectors. Vietnam’s agriculture still depends heavily on weather conditions.
Besides, traditional cultivation methods don’t bring high yield. With the
development of economy and society, human demands have gradually increased,
requiring an increase in quantity and quality as well. Hence, advanced devices that
can measure and adjust parameters such as temperature, atmosphere moisture,
nutrition to suit every single stage during the process of development of plants are

iii


needed. For the above-mentioned reasons, we have decided to research and design
“Automatic Watering System”.
3. Purpose for conducting the research
We wish to apply accumulated knowledge to research and design an automatic
watering system model in order to apply to Vietnam’s agriculture. We hope to bring
new methods to watering plants so that agricultural production can be more
effective.
4. Outline
- Overall introduction about the topic
- Introduction about components used in control circuits
- Designing automatic watering system
- Result and development orientation
5. Research method
In order to conduct the research, we use the following methods:
 Inheritance research results
- Inheriting researches by past generations on theoretical backgrounds
for programming and modeling software
- Inheriting researches applied in reality
 Research orientation
- Researching programming and modeling software on computers
- Seeking simple, easy-to-use and effective programming methods
 Test
- Conduct the test run repeatedly, check and find out mistakes then
perfect the system

iv

INDEX
Lời cám ơn
Opening part
Index

..........................................................................................................i
................................................................................................ ii
.......................................................................................................... v

Figures and charts ...................................................................................................vii
CHAPTER 1: OVERVIEW ................................................................................... 1
1. 1. Definition of ‘Automatics’ .............................................................................. 1
1. 2. The role of automatics in production ........................................................... 1
1. 3. How ‘automatics’ is applied in watering plants ............................................ 2
1. 4. Researches conducted in foreign countries ................................................... 3
1. 5. Domestic researches ...................................................................................... 5
1. 6. Domestic researches ...................................................................................... 5
CHAPTER 2: CONTROLLER ELEMENTS ....................................................... 6
2. 1. Central processing unit .................................................................................. 7
2. 1. 1. Board Arduino Mega 2560............................................................................ 7
2. 1. 2. Diagram of Board Ardunio Mega 2560 ports ................................................ 8
2. 1. 3. Technical specifications of Board Arduino Mega 2560 ................................. 9
2. 2. Receiver unit .................................................................................................. 9
2. 2. 1. Temperature sensor LM35 ............................................................................ 9
2. 2. 2. Humidity measure sensor FC-28 ................. Error! Bookmark not defined.0
2. 2. 3. Matrix keypad 4x4 ......................................Error! Bookmark not defined.2
2. 3. Display unit .................................................. Error! Bookmark not defined.3
2. 3. 1. LCD 2004 Blue .......................................... Error! Bookmark not defined.3

2. 3. 2. Communication module LCD 1602/2004 ...Error! Bookmark not defined.5
2. 4. Real-time unit ............................................... Error! Bookmark not defined.6
2. 5. Equipment controlling unit ......................... Error! Bookmark not defined.7

v


CHAPTER 3: DESIGNING PLANT WATERING SYSTEM ........................... 18
3. 1. Set up the problem for the system............................................................... 18
3. 2. Designing the mechanical parts ................................................................... 18
3. 2. 1. Estimating the needs of water each time and the ability for water supply .... 19
3. 2. 2. Dividing watering zones ............................. Error! Bookmark not defined.9
3. 2. 3. Calculating the main pipes .......................................................................... 20
3. 2. 4. Calculating the branch pipes, secondary pipes ............................................ 20
3. 2. 5. Selecting the watering method .................................................................... 21
3. 2. 6. Materials used in construction of watering system ...................................... 22
3. 3. Designing controlling circuit ........................ Error! Bookmark not defined.3
3. 3. 1. Designing the hardware ............................................................................ 243
3. 3. 2. Designing software .....................................Error! Bookmark not defined.4
CHAPTER 4: TEST AND RESULTS ................................................................. 25
4. 1. Testing “Display unit” .................................................................................. 25
4. 2. Automatic watering ...................................................................................... 26
CHAPTER 5: CONCLUSION AND DEVELOPMENT ORIENTATION ....... 27
5. 1. Conclusion ..................................................................................................... 27
5. 2. Limitation of the topic .................................................................................. 27
5. 3. Development orientation .............................................................................. 27
REFERENCE ......................................................................................................... 29

vi

FIGURES AND CHARTS
Figure 1-1: Watering Robot Droplet ......................................................................... 4
Figure 2-1: Diagram of units .................................................................................... 6
Figure 2-2: Pin diagram of board Arduino Mega 2560.............................................. 8
Figure 2-3: Temperature sensor LM35 ................................................................... 10
Figure 2-4: Humidity measure sensor FC-28 .......................................................... 11
Figure 2-5: Matrix keypad 4x4 ............................................................................... 12
Figure 2-6: LCD 2004 Blue ....................................Error! Bookmark not defined.3
Figure 2-7: Pin diagram of LCD 2004 blue ............. Error! Bookmark not defined.4
Figure 2-8: Communication module LCD 1602/2004Error! Bookmark not defined.5
Figure 2-9: Module RTC 1307 ............................................................................... 16
Figure 2-10: Pin diagram of Module RTC 1307...................................................... 16
Figure 2-11: 4-Channel 5V Relay Module .............................................................. 17
Figure 3-1: The hardware according to figure 1-1 ................................................... 23
Figure 3-2: Plastic box of hardware ........................................................................ 23
Figure 3-3: Interface of programming software ...................................................... 24
Figure 4-1: Manual mode ....................................................................................... 25
Figure 4-2: Time mode ........................................................................................... 26
Figure 4-3: Alarm mode ......................................................................................... 26

vii


CHAPTER 1: OVERVIEW
This chapter deals with the following parts: brief introduction about
automatics in agriculture, domestic and foreign researches on automatic watering
system models, and additional solutions to the research topic.

1. 1. Definition of ‘automatics’

Automatic systems which comprise automatic components are systems used to
control processes happening in the nature and life without direct interference from
human beings.
Automatic control systems are combination of physical elements which are
related to each other and used to monitor, adjust or control other systems.
Automatic control systems are very popular nowadays.
- Air conditioning systems
- Moisture adjusting systems
- Fire alarm systems …
In factories/plants:
- Automatic machines
- Automatic production and assembly lines
- Control machines operating based on programs, computers, robots, etc.
1. 2. Role of automatics in production
Thanks to mechanization and electrification, production tools and equipment
have gradually developed and perfected. Innovations in the material technology
field then electronics and information technology fields have created favorable
conditions for automatic technology to thrive which brings so many benefits to the
society.

1


In reality, when automatic technology is applied in production, results are
huge such as decrease in production cost, improvements in productivity and
production conditions, meeting high intensity requirements in modern production,
specialization in production, etc. Thanks to these results, competitiveness shall be
advanced, meeting production requirements.
In the near future, automatics shall play an indispensable part because it is not
only applied in production but also daily life. In production, it replaces humans

when it comes to hard, dangerous, toxic works and works requiring sophistication
etc. And in daily life, this technology shall serve various demands of humans. It will
be an indispensable means in our daily lives.

1. 3. Application of automatics technology in watering plants
Vegetation work is the agricultural production base and is a typical example of
modernization. All processes in agricultural production can be controlled
automatically in order to decrease labor force, increase yield, etc.
Although automatic technology was applied to watering for a long time, it
only developed in some developed countries. For developing countries, even though
agriculture occupies a high proportion in their economies, applying automatic
technology in watering plants is not popular. Today, with assistance from foreign
countries, developing countries especially Southeast Asian countries including
Vietnam have been applying automatic technology to life and production.
Nowadays,

with strong development

of

automatic

technology

and

achievements in microelectronics and information technology, automatics in all
fields become possible. It is possible to affirm that automatics have become a trend
in all industries of any country.

2


1. 4. Researches conducted in foreign countries
There have been many researches on automatic watering system in foreign
countries so far:
In early 1980s, Soviet Union (the old name of Russia) manufactured an auto
machine applied in its agriculture. While it was being operated, this machine could
observe land moisture, atmosphere temperature, wind force, etc. It could determine
watering method and water plants thanks to a machine that could produce artificial
rain.
Robot manufacturer Droplet has introduced watering robots integrated with
latest automatic technologies, cloud computing and some other connection services
allowing Droplet to be able to automatically observe injectors, adjust water volume
and watering frequency. Thanks to this, it can automatically water plants according
to schedules calculated by itself based on analyzing input date. Droplet is an
automatic injector that is able to adjust water to be injected from roots to trunks
within a radius of 9.14 meters. Before the robot automatically operates, what users
need to do is providing names of trees in the garden through a telephone or a tablet
wirelessly connected with the robot.

Based on the given information,

Droplet shall search information on the Internet by itself in order to determine water
volume

and

watering

frequency

suitable

with

each

kind

of

tree.

Moreover, Droplet also searches information about local weather conditions to
determine whether it is going to be sunny or rainy in order to calculate an
appropriate schedule. Israel automatic watering controller is easily programmed
according to users’ demands. Installation of the automatic watering system
according to advanced technology only requires some small programs, providing
the system with an input water source and leading injectors to positions needing
watered.

3


Figure 1-1: Watering Robot Droplet

There are two kinds of control: based on watering time and circle:
- Control based on watering time: Systems operate according to real time
shown in clocks

- Control based on watering circle: Systems operate according to repeat circles
of the time
Time and magnetic valve controllers:
- Auto controller: used to set auto watering time such as operating time,
operating duration, and time for stopping water or switching to new
positions. The rain sensor will help the machine to automatically stop
watering when it rains or moisture in the atmosphere is high.
- Magnetic valve: is device which receives and transmits signals from the
controller to injectors so that they can operate properly.
Watering systems’ operation principle: Watering time shall be set, when it
comes to operating time, the controller shall automatically transmit signals to
magnetic valves. Then these valves shall be automatically opened and supply water
for injectors. Users can set the watering time anytime they want.

4


1. 5. Domestic researches
There have been many researches on automatic systems conducted in Vietnam
so far and they have been also applied in reality. People created semi-auto watering
systems that helped save labor force and productivity was higher than when it is
done manually. However, this system still has many shortcomings and it needs
improving to have best results possible. In technology universities, students
conducted many research topics on auto watering system. But they also have many
drawbacks.
Multipurpose automatic watering system is a scientific work conducted by two
teachers from Hue College of Industry, Dr. Le Van Luan and MS. Le Dinh Hieu.
Main parts include a temperature sensor and land moisture sensor installed at a
poly-greenhouse for growing flowers and a controller programmed on PLC-S71200. When parameters shown in the sensors about land’s moisture or atmosphere
temperature at the poly-greenhouse signals that water is needed, this signal shall be

transmitted to the PLC controller. Then functions shall be automatically controlled
to receive and inject water based on installed injectors and automatically stop within
5 minutes after the temperature sensor or the land moisture sensor meets
requirements.
The multipurpose automatic watering system is product of a very good and
realistic idea realistic. It was experimented and brought good results.
1 . 6. Problems needing further research
Above researches have been applied for a long time. However, because of
their high prices, many people can’t afford to buy them. Therefore, the author
conducted a research on a watering system using a sensor for measuring atmosphere
moisture to determine watering time. This system is easy to manufacture and repair
and more importantly, it doesn’t cost much money …

5


CHAPTER 2: CONTROLLER ELEMENTS

Controller design has feature to control close/open auto electrical equipment
via temperature and humidity sensors.

System designed including 05 units:
- Receiver unit including temperature & humidity sensors, a Matrix keypad
4x4
- Processing unit Board Arduino Mega 2560
- Display unit with LCD
- Equipment controlling unit using Relay 5VDC to close/ interrupt equipment.
- Real-time unit (timer)

Figure 2-1: Diagram of units

Features of each unit:
-

Central processing unit: Board Arduino Mega 2560 controls total activities
of circuit such as follows receiving data to decode temperature and humidity

6


signals. Bringing displays to LCD and then giving signals for controlling
open/close (timer for open /close) electrical equipment.
-

Receiver unit: are sensors to collect signals from outside environment to
provide to Board Arduino Mega 2560 for processing, including: temperature
sensor LM35 and humidity sensor FC-28, there out we have Matrix keypad
4x4 to import parameters for controlling by hands.

-

Display unit: is LCD with 04 lines 20 characters to display temperature and
humidity of environment, time.

-

Real-time unit: Using Module 1307 to set up and adjust time of starting to
sprinkle and sprinkle time.

-

Open/close electrical equipment unit: using Relay 5 VDC to close / interrupt
active circuits of electrical equipment this unit receives signals from Board
Arduino Mega 2560
There out we have source unit provides supply current for total accessories in

circuits. It creates stable voltage that compliant with index about voltage and
current.

2. 1. Central processing unit
2. 1. 1. Board Arduino Mega 2560
Board Arduino Mega 2560 is integrated circuit controlling microcontroller
ATmega2560. It has 54 digital I/O ports (including 15 PWM ports), 16 analog input
ports, 4 UARTs (Universal Asynchronous Receiver – Transmitter), a Quartz Crystal
Oscillator 16 MHz, USB connection, a Electric jack, a ICSP header, and a reset
button. It contains everything is needed for supporting microcontroller; only
connect it to computer by USB cable or provide source with AC-to-DC adapter or
battery for performing.

7


2. 1. 2. Diagram of Board Arduino Mega 2560 ports

Figure 2-2: Pin diagram of Board Arduino Mega 2560

8


2. 1. 3. Technical specifications of Board Arduino Mega 2560
- Microcontroller:

ATmega2560

- Active voltage:

5V

- Outside source (request) :

7-9V

- Outside source (maximum) :

6-12V

- Current for each I/O port:

20mA

- Current for 3.3V port:

50mA

- Quantity of Digital port:

54 (15 PWM ports)

- Quantity of Analog port:

16

- Universal asynchronous receiver/transmitter UART:

4 UART sets

- Serial Peripheral Interface SPI:1 set (port 50-53) using SPI Arduino library
- Inter Integrated Circuit Communications I2C:

1 set

- Outside interruption :

6 ports

- Flash memory:

256 KB, 8KB used for Bootloader

- SRAM:

8 KB

- EEPROM:

4 KB

- Clock frequency:

16 MHz

- Length:

101.52 mm

- Width:

53.3 mm

- Mass:

37g

2. 2. Receiver unit
2. 2. 1. Temperature sensor LM35
Temperature sensor LM35 is a sensor type very useful to implement real-time
temperature measurement. Because it work correctly with small errors, and with
small size and cheap price also is a good point.

9


Figure 2-3: Temperature sensor LM35
Technical specifications:
- Input voltage from 4V to 20V
- Output voltage: -1V to 6V
- Power Consumption 60uA
- Output voltage resolution 10mV/oC
- High accuracy at 25 C: 0.5 C
- Output low impedance: 0.1 for 1mA of load
- Linear temperature change: 10mV/°C

- Accuracy in reality: 1/4°C with Room Temperature and Outdoor
Temperature 3/4°C around -55°C~150°C

2. 2. 2. Humidity measure sensor FC-28
Sensor to measure soil humidity, normally output will display at low-level.
When soil does not have enough water, output will display at high-level. Module is

10


able to use for auto water pouring. We can adjust sensitiveness of soil humidity
sensor (by adjusting blue rheostat on circuit board). Head part plugged into soil to
measure humidity, when humidity of soil reaches threshold value, output DO will
change the status from low-level to high-level.

Figure 2-4: Humidity measure sensor FC-28
Technical specifications:
- Working voltage 3.3V ~ 5V
- Have permanent hole to assemble conveniently
- PCB with small size 3.2 x 1.4
- Connection head uses 3 wires
 VCC: 3.3V ~ 5V
 GND: GND of outside source
 DO: Output of digital signal (high level or low level)
 AO: Output of Analog signal

11


2. 2. 3. Matrix keypad 4x4

Matrix keypad is a soft plastic keyboard including 16 buttons. This keyboard
linked to Board Arduino and programed for displaying on LCD.

Figure 2-5: Matrix keypad 4x4
Technical specifications:
-

Voltage and operating current: 15VDC and 100mA

-

Connection gates: 8 gates

-

Working temperature: -20 ~ 40°C

-

Size: 77 x 70 x 0.8mm

12


2. 3. Display unit
2. 3. 1. LCD 2004 Blue
Bule text screen LCD2004 uses driver HD44780, be able to display 04 lines
with each line including 20 characters, screen has good reliability, very common,
many sample code and easy to use, suitable for newbie and people implement
project.

Figure 2-6: LCD 2004 Blue
Technical specifications:
- Operating voltage: 05 V.
- Size: 98 x 60 x 13.5 mm
- White texts, blue background
- Distance between 02 ports need to be connected: 0.1 inch, easy to connect to
Breadboard.
- Name of ports written in backside of LCD screen to support connection,
arranging electric wire.
- Have led light at background. Be able to use rheostat or PWM for adjusting
brightness to reduce power consumption.
- Be able to control with 06 signal wires.
- Characters sets is support in English and Japanese.

13


Figure 2-7: Pin diagram of LCD 2004 blue

Including:
- VSS is grounded port
- VEE port selects contrast. This port selected via 01 rheostat 5K a connection
head VCC, a Neutral wire.
- Port VDD connects to Positive source
- Port selects registers RS (Register Select): have 02 registers in LCD.
 If RS=0 in writing command mode such as follows deleting screen,
open close pointer.
 If RS=01 in writing data mode such as follows displaying characters,
numbers on screen.

- Reading/ writing ports (R/W): input reading/ writing allow user to fill
information on LCD khi R/W = 0 or reading information of LCD when
R/W=1.

14


-

Allowing port E (Enable): allowing port E used by LCD to complete its data.
When data is in that port we need a frequency from high-level to low-level at
this port for LCD completing data, this frequency must have width at least
such as 450ns.

-

Port D0 – D7: This is 08 ports of 08-bit data, used for sending to
information LCD or reading content of registers in LCD.
2. 3. 2. Communication module LCD 1602/2004
To use types of LCD with driver such HD44780 (LCD 1602, LCD 2004,...),

need at least 06 ports of MCU connected to ports such as follows RS, EN, D7, D6,
D5 and D4 to communicate with LCD. However, with communication module LCD
to I2C, only need 2 ports (SDA and SCL) of MCU connected to 02 ports (SDA and
SCL) of module, it can display information on LCD. There out we can adjust
contrast by assembling rheostat on module.

Figure 2-8: Communication module LCD 1602/2004

Description of ports (according to order):

- GND: grounded port 0V
- VCC: source 5V
- SDA: Analog head 4
- SCL: Analog head 5

15


2. 4. Real-time unit

Figure 2-9: Module RTC 1307

Real-time Module DS1307 (RTC) has feature to store date information day,
month, year as well as hour, minute, second, it works as a watch and export data via
I2C protocol (Inter-Integrated Circuit). Module designed attaches with a battery of
watch has ability for storing information up to 10 years needless to provide source
5V from outside. Module attached with EEPROM AT24C32 has ability for storing
information up to 32Kbit.

Figure 2-10: Pin diagram of Module RTC 1307

16


Description of ports such as follows:
- X1 and X2 are oscillate input for DS1307. Need oscillate of quartz crystal
32.76 KHz.
- Vbat is power supply for chip. This source from 2V-3,5V. This source helps
chip perform continuously when does not have source Vcc and DS 1307 still
performs according to time.

- VCC is source for communication I2C. Voltage provided is 5V according to
standard and used together with microprocessor. If we do not have Vcc but
we have Vbat, so DS1307 still performs as normal but without writing and
reading data.
- GND is general ground for Vcc and Vbat
- SQW/OUT is an output create oscillation frequency (Square wave). This port
does not affect real-time so we do not use this port in real-time and ignore it
- SCL and SDA are 02 data bus of DS 1307.

2. 5. Equipment controlling unit
Equipment controlling unit uses Relay to close / interrupt electrical circuit
this capacity received controlling command from Board Arduino Mega 2560.
(Using low voltage open/close high voltage)

Figure 2-11: 4-Channel 5V Relay Module

17


CHAPTER 3: DESIGNING PLANT WATERING SYSTEM
3. 1. Set up the problem for the system
The automatic plant watering system has been widely applied.
By automating the plant watering system, it will increase the efficiency of
cultivation such as: labor hours reduced, water saved, plan productivity increased.
However, in order to reach highest efficiency, it needs to be considered carefully in
term of plant properties and local conditions.
An automatic plant watering system contains:
- Water supply for the system.
- Water pump, electromagnetic valves.
- System of main and secondary pipes.

- Sprinkler heads (may be not applicable depending on watering methods).
- Control box which automatically shut the water pump and electromagnetic
valves when necessary.
Proposing the solution for the automatic watering system
Options to decide whether to open/shut the watering system as follows:
- Humidity > 90%, the system are not operated.
- Humidity of 85-90%, watering in 10 minutes
- Humidity of 80-84%, watering in 15 minutes
- Humidity of 75-79%, watering in 20 minutes
- Humidity < 74%, watering in 25 minutes.
These options are subject to change depending on the region, plants, seasons and
weather.
Designing the automatic timer, the system is operated when the set time come,
the pump is turned on and turn off depending on the humidity.

3. 2. Designing the mechanical parts
The watering methods which involved watering pipes have the same
calculation principles of drainage and hydraulic pipes. These are: Determining the
18


watering zone, water supply, water demand for each type of plant, area and terrain.
From these parameters, we will calculate the diameter of main pipes, secondary
pipes, branch pipes, laterals, velocity of water flow in the pipe, water pressure in the
pipe, the length of the pipes, the connectors (swan-necks, T pipe connector, valve,
pipe curve connector ...), the number of spraying heads, bottom base, connector
pipes etc… and finally make the list of quantity of materials, calculate minimum
supplies costs, installation fees etc. …
3. 2. 1. Estimating the needs of water and the ability for water supply
Depending on each plant, we determine number of watering time, water

needed per time. The number of watering time depends on the properties of plants
and dampness of soil.
We only need to calculate the approximate parameters on the number of
watering to find the amount of water needed. In production, number of watering
time should be adjusted according to actual soil, weather conditions.
Water needed per time is important parameter for calculating and designing
watering system and calculate amount of water. In reality, the water plants need is
less than the amount we provided, so that the amount of water needed depends on
the watering methods. In general, the water demand for a perennial plant per time is
ranged from 5-10 liters (drip watering); 15-20 liters (jet watering), 30 to 40 liters of
water (ditch watering, sprinkler watering).
3. 2. 2. Dividing watering zones
If only a small area need to watered, it will be one watering zone, but with a
larger area, it must be divided into several watering zones. If the divided watering
zone is too large, the capacity of water pump and diameter of main watering pipes
will be increase significantly; this leads to no economic benefit. The best method is
to water each watering zone one after another.
When dividing watering zones, it must be drawn up to present the shape and
area of each watering zone, the length of the edge of the watering zones, drawing
the tree line and the length of each row of trees so we can calculate the number of
trees planted in each watering zone, to find the diameter, length of the main pipes.
19