The main difference between pole beans and bush beans should be obvious. Pole beans climb poles. Bush beans are bushy. To complicate things, bush beans are more common in commercial agriculture because they are more adaptable to harvesting machinery, and they are most productive in a brief season, so are more efficiently harvested all at once rather than throughout summer.
Pole beans are generally more popular in home gardens for the opposite reason. They will not produce all at once, but will instead produce enough somewhat continually until the end of summer. Some varieties can climb past second story eaves, so should be confined to reachable trellises or other supports. They are annual, so the tangled thicket of vines that forms on top is no problem.
Most pole beans, which are also known as green beans, string beans, snap beans, French beans and haricot vert (French for ‘green beans’) are varieties of Phaseolus vulgaris. Some heirloom varieties of the original string beans produce beans with annoying ‘strings’ along one side of each bean. Dried beans are different varieties. Regular harvesting promotes continuous production.