May. Vines are trained to either wires or poles from 6 to 9 feet in length. Spider mites are the major pest of pole beans. Some gardeners may want to try edible soybeans, which are nutritious because of their high protein content. They can be used as a fresh green bean, dried and roasted as a nut, or ground into flour. Plant soybeans in rows 2 to 3 feet apart, with plants spaced 2 to 3 inches apart.
Bacterial blight appears as translucent water-soaked spots, which with age turn red around the rims.
This fungal disease appears as circular, dark, sunken spots on pods and stems. The fungus overwinters in the seed and in bean refuse. Spores are scattered from plant to plant by wind, rain, and people working in the garden, especially when the foliage is wet. To control, use disease-free seed and allow two years rotation between bean plantings. Rust Bean rust is a disease chiefly of the leaves.