For me it's growing outdoors in soil and the nutrients are rain water
The current wife and I have been growing this way for about 15 years, we are fortunate to have a large area and feed ourselves and family, get a bit fed up with beans in September though......
We put the hard work in the winter, spreading shit that has been donated all year, I think the recent upsurge in gardening is great, but you have to have it in your mind that it's not just about sowing a few seeds when the weather is nice, you have to put the work in and prepare the ground, it's a lot more easy that way.
Well I do have to intervene with bugs and certain environmental factors but I think if left to the plants own devices over the years it would evolve some kind of defence, but that is thinking without human intervention.
We are talking about all plants and not just cannabis?