While we're on the subject of beans, I found a new type of weed all over my garden fences this past summer. At first I ignored them, assuming they were the little blue wild morning glories. But then I started seeing little bean pods and so I checked closely and the plants definitely had nice little pale purple blossoms. The leaves were three-part leaves, and each leaflet was heart-shaped but with a rounded point and no bigger than about 1" by 1 1/4". This was a vine and the leaves were maybe 8 to ten inches apart, not thickly grown. The bean pods were 2" to 3 1/2" long and quite narrow, and rounded, not flat.. I would have loved to gather them as a wild food, but I would NEVER assume they were edible.
Since they were only on fences, they must have come from birds pooping the seeds, but I can't imagine how they got here and where they are from. I've lived here since 1977 and have NEVER had this growing anywhere before this year. So they must have been dropped by birds the year before and then grown from when they germinated at the beginning of this last summer.
So I guess I've discovered a neat little miniature bean vine. I wonder if they will grow again this next summer from dropping their pods at the base of all my garden fences?
It would be great if you could get that plant identified! A self seeding volunteer bean could be very useful. However, like most volunteer plants, it might not be something you want to encourage lest it start taking over.
In the past 15-20 years, we've had several "new" (as in, never saw them before- and I know pretty well every plant that grows on our farm) weeds pop up. After battling purple loosestrife and henbit for years, my new policy when finding a new plant is essentially "nuke it from orbit to be sure!"
If I find one that might have food or medicinal value, I'll try moving it to an isolated bed or even a big pot, until I see it's habits.
But a self seeding bean could be cool... I had both peas and beans volunteer in the garden this year after we finished harvesting and tilled down the dead plants. It was great... they formed a dense, weed blocking carpet, and will add organic matter next spring... plus, since they are legumes, they added some nitrogen to the soil. But I've never seen volunteer beans or peas in the Spring. For that matter, despite the fact that we get hundreds of volunteer tomato plants every spring (and they often produce very well, albeit a bit later than the ones I start early and transplant), I've never seen a volunteer pepper plant. And I wonder why!
Summerthyme