Buckwheat Cover Crop Size Requirements

Hey all,

So I'm lucky enough to be granted a 2'x2x16' Raised Bed, and would like to use as much permaculture design as feasible at this point. I want to do a fruit/vegie garden, and was thinking of adding some buckwheat in as cover crop. Would using buckwheat be feasible/worthwhile to do in such a small space? Any recommendations would be much appreciated.

Cheers,
Kirk

Buckwheat pops up everywhere at my place; I only needed to plant it once!
The insects love it and if it's too tall, in the wrong place or whatever, I just pull it out and leave it lying on the garden
From what I've seen, buckwheat can push through mulch, which suits me as I don't have to fiddle about with mulching around plants.

Thanks! I appreciate your help.