Green beans, string beans, wax beans, and snap beans are all terms to describe pole or bush beans. These beans differ a bit in color and shape but work just fine in pickle recipes. Besides green, you will find light yellow and purple hues in the market, just know that purple beans lose their color when cooked. One bean to avoid for pickles is a French variety called Haricots verts, a small, thin variety. These don't hold up well to pickling.