CFB yellowing leaves

My beans have a couple of chicken manure pellets in the hole at planting out - if I remember. After that. they're on their own. I can't be doing with all this feeding/watering malarkey.
PS, They'e still green, I checked yesterday.

Must be some other reason then, I have watered them rather enthusiastically,  might be too much.  Anyway I'll give them a feed of something today perhaps but I fear the damage is done.  Luckily I've got more beans than I know what to do with.  In my imagination I picture you with your thumb to your nose wiggling your fingers and going nah na na na nah nah, in the nicest possible way of course