Fear of frost is responsible for this classic French bean.
In the mid-19th century, when the French were perfecting strains of dwarf beans from England, a farmer outside Paris named Gabriel Chevrier was worried about frost. He was growing white dwarf beans, and the chilly spring and autumn of 1872 almost certainly promised a cold snap and early frost that year. So, he pulled his bean plants out of the ground early, hoping they’d continue to mature as they dried in the barn. Imagine his surprise as he shelled his first beans a few weeks later and found pearly green beans instead of white. He liked their delicate taste enough to repeat his method the following year and the next, refining his growing technique over six years. The smooth, light beans were an instant hit with French chefs, and in 1878, the National Horticultural Society of France allowed Chevrier to name his beans.