I don't like them either - for Snadger's reasons - if you don't keep them wet they constrict the roots (the point of them is that the roots can grow through.) If you keep them wet enough for this you can get green flurp on the top of your compost as it's too wet for the compost.

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It takes more oil than vinegar to make a good salad dressing.

vegheaven.blogspot.com Updated Sept 7th 2008