A nice healthy bean. For this you need well-nourished plants.
To have well nourished plants, one needs calcium and nutrients.
Here's one way to arrange that - EGGSHELLS.
One thing I started doing a few months ago was to start saving eggshells. I eat a lot of eggs as the second major meal of the day. I read somewhere that calcium (and also trace elements) in eggshells is a good element for plants, and that eggshells rank up there with rock dust as a source of nutrients. However, the eggshells have to be ground in a food processor, and then put in the soil where they will very slowly dissolve when one adds an acidic solution to the soil (for example, when one uses tea leaves as mulch, or adds grey water in the forms of tea-leave-water or vinegar-water that one has used to clean salad leaves). Its not a fast-acting nutrient, but a slow release.
(Unfortunately the water from the boiled eggs isnt really worth much in terms of dissolved calcium, so you have to get the eggshells themselves).
To apply the eggshells this time, I stored the eggshells in the freezer in a ziplock bag. (internet sites advise washing them and cooking the shells in the oven before powdering them, but I think thats just too arduous). When you are ready, take them and blend into fine grains in a food processor (do it with the frozen stuff, it is all ok, and while they are frozen they dont smell at all - its far less smelly than once they thaw). Then add in the pulverised egg shell bits to tea leaves and add as mulch (see photo). I did this a few weeks ago, and it seems to have given some plants a growth spurt.
This is what it looks like -
(apropos of nothing eggshell related, a flourishing corn plant head from my garden).