Good Question: Material for a Raised Bed?

Good Question: Material for a Raised Bed?

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This question is actually from my dad:

He really wants to build a few raised beds in the backyard to accommodate my mother's ever expanding vegetable garden; however, he wants to do it on the cheap and he doesn't really want to use wood, which he worries would rot over time.

He's thinking that he might want to use rocks and stones of some sort to build the beds. I suggested that he check freecycle and Craigslist for freebies. However, that whole scene is a little less active in this small-ish Southern California town.

We also suggested a no-dig garden, but he seems set on raised beds.

So I thought I'd check with readers here -- how would you build a raised bed on the cheap, and not using wood?

image via stewickie; Flickr.com

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