I never had really luck with mail order plants. The only one that's ever worked out is an Egyptian walking onion.
It will grow a small bunch of onions on top of the stem, then, the stem will kink, so that the little onions will touch the ground and then grow a new plant, hence the name.
The onions have a pretty harsh flavor, but it's a neat plant, and I had it for about 10 years now.

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