> But I always wondered why stuff that literally grows on trees isn't cheap and abundant. American grocery stores sell bananas grown outside on trees for liter

> But I always wondered why stuff that literally grows on trees isn't cheap and abundant. American grocery stores sell bananas grown outside on trees for literal pennies each. Dirt cheap tropical fruit, arguably the CIA's finest contribution to American society.. Anyway, mirrors. Mirrors don't multiply light, they only bounce it. 1 square meter of mirror can only bounce a square meter of sunlight. If you have a 5 level parking garage, each level 1000 square meters, then you need 5000 square meters of mirror. What did any of this accomplish, vs simply building a single layer regular old greenhouse? Remember that most surface areas of most countries is not urban so in most cases there's no reason to grow food in urban areas.