Found out that It may be beneficial to have a RTC.  Found out that microelectronics can put into a deep sleep mode and wake them up when you need them to do something. I will be activating the device between 5:00 to 6:00am/\pm to take moisture reading and decided if the garden bed needs to be watered. Furthermore having the device only awake for a few hours per day a save energy on my 12v battery powering the device.