Drying bean cultivars are primarily bush types, though there are pole types as well. That said, ANY bean can be used as a drying/soup bean, but the varieties sold specifically as dry beans are selected for flavor and production for dry storage. If your bean selection is a half-runner or ple type, make sure to provide trellising.
Beans need plenty of sunlight to grow properly, so try to choose an area of your garden that receives full sun for your planting site. Since green beans do not do well in heavily-moist soil, you should avoid shaded locations, since shade tends to help soil retain moisture for prolonged periods.
Beans thrive in loamy soil, so if your garden has heavy clay soil or sandy soil, you should amend it with organic material before planting your green beans. Loamy soil is dark and crumbly. Test the soil by squeezing it in your hands. Clay soil stays in a ball and sandy soil falls apart completely. Loamy soil will hold its shape initially yet break apart when touched.
Beans do not require a vast amount of nutrients, but a light application of fertilizer can help your plants produce a better crop. Use a shovel or trowel to mix the fertilizer into the top 3–4 inches of soil. 10-20-10 fertilizer is slightly richer in phosphorus than in nitrogen or potassium, so it is good for producing a strong crop yield. If you use a fertilizer high in nitrogen, then your plant will grow a lot of leaves but few beans.
Plant each seed 1–2 inches deep in the ground. Each seed should also be about 3–6 inches apart and covered lightly with loose soil. If you're planting multiple rows of beans, leave 1–2 feet of room between each row.
Apply mulch to the soil where beans are planted. Standard wood chip mulch or straw works well with green beans. Mulch can prevent the soil from getting too cool or too warm, and it also helps the soil retain moisture.
Excessively hot weather may cause the plants to drop their blossoms and pods prematurely. If you live in a region known for particularly hot summers, you may need to put a stop to your green bean growing season during the hottest months.
Unlike with your regular green bean plantings where you will harvest your beans often and before you see much bean development in the pods, with drying beans you want to leave the beans to mature and then ultimately dry on the plants for the best flavor and nutrition. Plan your plantings to leave at least four weeks for the beans to dry on the plant.
After you separate your beans from the dry pods, spread your beans out to continue drying for at least two more weeks. We strongly recommend you freeze your beans for about two weeks before storage to kill any possible bean weevils that might be present.