I've been wondering about this all year, but haven't thought to ask about it yet. I used one of those big blue tarp-like Ikea bags to bag up the moss-infested top soil from the neglected front flower beds when I bought my house last summer. I thought that keeping the light out would help kill the moss and maybe help get it ready for re-use one of these days, so I covered it up with a cheap tarp and just left it in an out-of-the-way corner. At any rate, the bag itself has held up to being outside all summer surprisingly well, which leads me to wonder if it could be used as a sort of grow bag. As they are cheap and huge, it seems that they might be a cost-effective way of getting a big container good for planting stuff like turnips or celeriac. Has anyone tried such a thing? Do you think it would help keep the slugs/snails out of the vegetables?