I'm sorry, I can find some suggested figures for snap beans, but not for dry beans.

I'm afraid that its going to take some trial and error to figure out what kind of yield you're likely to get from a given feet of row or square footage of bed and compare that to how much your family eats in a year.

My household of 7 could go for years not eating a single black bean because we don't like them. But yours might eat 5lbs or more per week as a mainstay of your diet.

Wish I could be more help.

I suggest that you plant as many as you have room in your garden for. Dry beans last a long time in storage, so having too many at once probably won't be too bad of a problem.

And yes, as the previous commenter said, it depends on how often you eat beans. I eat a lot of beans, so I don't actually manage to grow all the dry beans I can eat and end up buying some at the store anyway. The ones I grow are better than the store ones though.

I agree with the comments above; to answer this question, Ecopal, you need to start by estimating your annual usage, and how much of that total you intend to grow. If you eat a lot of dry beans, it will require a fairly substantial amount of space to grow a year's supply.

There was a good discussion of bean spacing in the thread below... which I wish I could move here.

Here is a link that might be useful: Talk to me about beans