Just from a short reading, I think this is all doable on the platform. But I will say that (1) possibly it will not fit entirely within ONE Arduino, and (2) you might find some good design benefits from implementing it as a series of subsystems like your list.
If you get familiar with the Arduino development a little bit, work on implementing one subsystem that does watering, one that does grow lights, one that does temperature monitoring, and so on. Then you may make a "mastermind" Arduino that can manage each subsystem according to a master schedule or a master set of rules.
In the meantime, each subsystem can be improved without affecting the rest of the project, and can apply to more situations than habanero peppers. Someone wants perfect tomatoes outdoors, they don't need the air purifying subsystem, but they still want the watering scheduler. Mix and match. And so on.