I read that square foot gardening is less expensive than normal, how is that?

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My new square foot garden. 4 x 4 foot box. Planting tomorrow!

Question by Okc-Bro: I read that square foot gardening is less expensive than normal, how is that?
Once you figure in the cost of the lumber and all the other materials you would use making a raised bed (soil, amendments, etc) how can this be? Yes, it requires less work, but how is it less expensive?
normal as in in the ground.
Thanks Cat for all the details

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