Here's my biggest bean so far.

Could be a lack of light. Your garden seem close to the trees. Also you have sown them quite far apart. I think you have put them twice as thick.

Actually that spot gets pretty much full sun - from about 11am to 8pm this time of year.

I initially sowed every 3" but then thinned to 6", which is what the directions said to do. But after doing that, I wondered why they couldn't be a little closer. Seems like after looking at other pictures, most folks plant fairly close together?

I have a small half row of bush beans which you can barely see behind the leaves in this picture (blurry). I also planted them every few inches but I think I may need to thin those too. Do you think they could be transplanted instead?

Beans don't transplant well, and if they are planted closely, the effort to do so would probably damage the remaining plants. Not saying that it might not work if carefully done, but I would recommend against it.

Those vines definitely look much thinner than normal; there should be more branches sprouting from the main runner. While beans prefer full sun, I don't suspect shade alone is the cause... I grew some pole beans in half-day shade last year, and the vines still filled out & produced a fairly decent crop.

My first guess would be the soil, especially if that is newly cultivated ground. If you have not had the soil tested, I would recommend doing so, then amending the soil based upon the lab's recommendations. If there is a pH problem, you probably won't be able to fix that until next year... but if there is a nutritional deficiency, an application of fertilizer might be able to improve plant health this year.

I would also recommend a thick layer of mulch around the plants and over the irrigation lines, to preserve moisture & to increase the water penetration into the root zone. In my garden, it is amazing how much beans benefit from a heavy layer of mulch... they languish if I am late laying it down, and become visibly greener 1-2 days after mulching & watering.

Thank you! I actually have some extra mulch I was planning to put in there tonight while I add the last of the missing strings and thin out the bush beans. Good to know that it's a good plan. :)
I also have some extra compost so perhaps I'll add that in there. Maybe I'll be able to tell a difference between the new plants and the old after doing so. The new ones are just barely at string height now so maybe I can catch it early enough to make a difference. Fingers crossed!

Also yes, this is newly turned ground. I did do a soil test prior to planting, and it was on target. But we've also had some crazy weather and I have no idea if that has anything to do with changing any nutrition content of the soil or not. I haven't added any fertilizer or anything else since planting.

I'll try the mulch/compost tonight!

I would be tempted to add some extra beans to those rows, even if they are bush beans.

For next year (or even for this year) some manure or compost would definitely help.

Linda

I've added more compost and mulch, so we'll see what happens. The vines growing on the other side of the trellis appear to be much fuller and healthier than what is shown in the picture above, and they are sending out side pieces that are attaching to the adjacent string.

The beans I've planted recently are shooting up like crazy and so far they all seem healthy. Thanks for the advice folks, and I'll post a follow up pic soon.

Next year sprinkle innoculant on the beans at planting time. It increases production. Good nurseries carry it.