Monitoring plant health is very important for their fast growth. In this busy world, people usually forget to water their plants which leads to bad growth and health of their plants.
We have implemented a plant monitoring and watering system using evive which continuously monitor the moisture, humidity and temperature of the plant. When the moisture level in the soil goes down to a certain threshold, it automatically starts watering the plant. The notification and the moisture level is shared to user using telnet through WiFi.
Before we move to mount the soil moisture
sensor, we will go through the principle of soil moisture sensor. There
are 4 pins in the sensor:
Pin1: VCC (5V DC)
Pin2: Ground (0V)
sensor provides both digital and analog output which can be used for
different purpose. The digital threshold can be changed using the
potentiometer. So id we use digital output then we will have only two
moisture levels. We can define one moisture level as pump 'TURN OFF' and
the other level as pump 'Turn ON'. But we have a disadvantage here
using the digital output. Whenever the motor starts, and the moisture
level increases near sensor and crosses the threshold, pump will be
switched off. Thus, watering will be for very short period of time and
water will not reach into deep roots.
Other option is to use
analog output. Sensor returns analog value between 0-1023, where 0 is
for wet soil and 1023 for dry soil. Here we can set two thresholds, one
for starting the watering and one for stopping.
For this project we are using analog output of soil moisture sensor.
Temperature sensor LM35 -
The temperature sensor will print the temperature of the room on the evive's
screen. LM35 sensor has been used for this. If you are using the
temperature sensor for the first time then you may follow this code
which prints the temperature around the sensor on the serial monitor in
just join the VCC in 5 volt of evive and GND to ground and output to any analog pin we done it in A0.
Humidity sensor provides the information humidity level of air around the plant. It has 3 pins,
sensor detects the humidity of the air around it. It has three pins
that are VCC, GND and analog pin. Just connect the VCC to 5 volt and GND
to ground and analog pin to A2 or whatever you want.