How safe is hydroponic growing?

It depends on how complex and what you want to grow. Generally, it should be fairly easy, the thing you have to watch is the controlled amount of nutrients being supplied to the plants. I would recommend growing in water first, as it seems to be the best option here. On the market, there is a product called "The AeroGarden", where herbs and small produce is grown in pods, in a water housing system. I suggest you google and research what you'd want to know.

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