Too little water?
I have beans planted in large containers. I usually water in the morning. My plants are entirely yellow (stem, leaves and leaf veins). I purchased organic fertilizer 1-3-2 and added, which I think burned the leaves. Last night around 4pm I checked and the soil was dry. Could my plants be under watered?
Yellow leaves are usually a sign of underwatering. When I water any container plants, when the temperature gets very high during the day, I usually give them a good soaking at night instead of in the morning. You could also put a light layer of mulch in the containers to help preserve the moisture. If they still get dry, water only the soil (not the leaves) sometime before noon. This article will give you some tips on caring for bean plants in containers: