Not daft at all CH. I too have long wanted to grow some sort of grain, and have planned it for next year at last. Initially, I was interested in wheat as a grain and also as wheatgrass, the young shoots, and the latest superfood juiced drink etc. Wheat or barley were the obvious first port of call, and then I went off on a wil goose chase looking at hops and all manner of interesting stuff.
But the more I looked into it and what my needs actually were, I plumped for buckwheat next year, having read several accounts from United States small farmers and homesteaders, and my having used it as a humble green manure for years. Also the grain needs to have several uses as I have no idea how much "flour" can be processed.
Not a wheat of course, and not strictly a "grain" possibly, but it serves the same purpose in food.
It's one draw back is it's lack of gluten as a bread flour, but that can be overcome, and I have always only used 20% maximum buckwheat flour in bread recipes in any case.
But look at it's advantages. It's main plus for me is I already use it as a handy rice/couscous type dish, which wheat isn't used for. It can be used as a cereal, toasted sprinkle, sprouted, pastry and bread baking, and an American favourite pancake flour. Almost any use you can think of. It matures to seed really quickly in 3 months. It needs no fertiliser, in fact will grow on virtually any soil. Virtually no pests whatsoever, and attracts beneficials to die for including honey bees big time. It can be processed into it's de-hulled seeds really easily apparently with a broom and sheet. It's properties as a green manure include for weed suppressing and digging in organic matter/soil conditioning. And apparently businesses are even using it's empty hulls to make trendy neck saving pillows. All that is too much to resist.
Most of those homesteaders reckon a useful annual crop can be gained from 20 sq meters... that's fine for me. So, the plan is to sow 40 sq meters after the last frost, dig in half of that as a green manure before it sets seeds, and leave the other half to mature and harvest. All the inevitable seeds left in the soil after harvest will be left to grow again as a second quick green manure crop to dig in come the end of October. All waste vegetation from harvesting will be composted. Perfect.
I reckon on using 500gms of seeds, which ain't that cheap as a horticultural product, almost £8
. But I already buy 500gm bags of raw buckwheat seeds/groats as a food from a local health food shop for £1.80... so I have a bag put by.
Just some thoughts for you to consider. Good luck with what ever grain you grow.