The system will be even smarter by incorporating more sensors to be a more comprehensive system. For instance, notifications to cellphones for the level of soil moisture, cellphone control that's similar to Apple's Homekit, etc.
Deeper incorporation with IFTTT. For instance, getting access to the weather channels' data, knowing exactly what time is going to rain, and preparing predicative mechanisms.
Multiple colors of LEDs indicating different states of operations.
There can be backup mechanisms. For instance, what if soil moisture sensor malfunctions? There should be a secondary sensor that prevents malfunctions from happening.
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