Answer: If the plants have wilted suddenly, there may be a root problem, or a disease has gotten a foothold. Since they're so far gone, I'd pull them up and remove them from the garden. Just for general information, most beans grow best at air temperatures of 70F - 80F and soil temperatures of at least 60F. If the soil is soggy, or cold, the plants will not thrive. They also require full sunshine all day.
I'd harvest whatever is being produced and then pull the plants up. You can plant beans again in the spring, in a different garden site. Be sure to prepare the soil well by adding lots of organic matter to help retain moisture and release nutrients to the roots of your crops.
Q&A Library Searching Tips