Automatic plant growth model.
Hydroponics is a type of soil less agriculture. Soil looses its nutrients and fertility with time, so to avoid that we can use Hydroponics. Plant growth and nourishment can be improved and control too. Plant which can grow only during a specific time of the year and be grown throughout the year. We can also monitor the growth of the plant, nutrient level of the soil, moisture contained in the soil and the amount of light received.

This project is a model of the actual system. Here we are replacing soil with cocoa powder. We can control the moisture and nutrients contain of the cocoa powder easily with respect to normal soil. In this project we are controlling only three criteria for plant growth i.e. moisture, light and temperature.

For our model we are using the specification of a lettuce plant

Temperature :- 25 to 30 degree Celsius.
Humidity :- 50% to 80%.
Light intensity :- 250 photons per sec.
For our model we are using an array of 3mm LED connect in series and parallel. We have used 16 LEDs 8 red LEDs and 8 blue LEDs. An array of 4 LEDs in series requires 12v power supply. So we are using an external power supply of 12v. To control the LEDs with help of Arduino we are using an optocoupler IC 4N35. For the information of the light intensity we are using light sensor with LDR. For better performance we can mount photodiode sensor. We have converted the reading from the light sensors into photons per sec using the code in Arduino.”