Got my automation mini hat working now. Yay! excited to write this after a gap. Completely got delayed due to various circumstances, but I just don't want to give up.
My plants didn't sprout properly due to 2 reasons one the seed I chose was spinach which is a spring crop unfortunately and took more time to come out due to cold winter here in Bengaluru.
The second reason is the soil used was dense and might pressurise the seeds to stay in maybe 
So I'm just documenting my progress and will continue to do even if the contest ends. 
So let's get into the control system:
I'm going ahead with a modular approach rather than a big system with a lot of wires and sensors. I'm dividing big 1m by 1m cube into 9 individual small blocks which are cells.
So I'm working with one particular cell now. The reason for dividing them is to grow different veggies and plants in different cells. Also, it will be easy to control individual cells.
THE CONTROL SYSTEM
Water, Light and ventilation are 3 major things a plant needs to survive, to make the system more efficient I'm going with LED lights and DC pumps rather than AC one's as the required water thrust will be lesser
and can be made battery operated.
This will be the simple and final architecture diagram for the system
Parts used here as follows:
1. LED Lighting
2. FAN for the ventilation
3. Pumpset for the water supply [12VDC]
4. Raspberry Pi
5. Automation Hat mini