For asparagus it is common to buy bare roots from a garden store or catalog and plant at the crack of spring in a deep well prepared bed. Artichokes I have grown from mail order seed, but many garden stores will buy starts. They grow fast in a hot site.
I just bought organic Japanese yams at my local asian supermarket, CAM. They had ginger as well, but I didn't know where/how I would plant that.
The yams I bought to grow for the greens, as they are said to have a superior flavor.
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