Who is that you feel the need to explain this to? How would they know you have an indoor greenhouse just by talking to you on the phone. Please dont take this wrong, but if you are this paranoid maybe growing isnt for you. I'm not saying it is wrong to be cautious and to cover your ass, but sometimes if you act too careful and evasive you might as well wear a sign around your neck saying I AM GUILY OF SOMETHING!!! And always answer a question with another question. For example: your soil PH question. If they asked you what you are growing, ask them if the PH changes with the type of plant grown. Is the PH different when you plant tomatos than it is when you plant peppers? This will usually get the point across that it is none of their business and they should just answer the damn question. Good luck and lets overgrow Big Bro.

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Keep your grow to youself, or everyone will get to see it on the news.