Bush beans need full sun and well-drained soil with plenty of organic matter. Amending your bed with an inch or two of well-aged compost before planting can help your beans produce a larger crop, but avoid high-nitrogen fertilizers, since too much nitrogen can cause beans to over-produce leaves and not put much energy into flowers and pods.
It’s a good idea to inoculate your bean seeds with legume inoculant, to ensure the plants have all the symbiotic microbes they need to help them fix nitrogen. These bacteria are naturally occurring in soil, but may be in low numbers in some gardens, particularly areas that have been recently converted from lawns, or where the soil is depleted. The easiest way to apply legume inoculant is to get your bean seeds a little wet in a bowl or bucket, then sprinkle the powder over them, mix with your hand, then plant right away.
Plant bush bean seeds 1 inch deep and 1 to 3 inches apart in rows 1 to 2 feet apart. Thin the seedlings to 3 inches apart once they get their first true leaves. If you started with good, rich soil, the beans shouldn’t need any further fertilizer. Make sure they get about 2 inches of water per week. Keep an eye out for pests like Mexican bean beetles (which look like large orange ladybugs, or bright yellow larvae) and pick off any you find. Beans can fall prey to many diseases, particularly in hot and humid weather, but often bush beans will “outrun” the diseases and produce a crop before they succumb. Plant successions every 2 weeks throughout the summer until 10 weeks before your first frost for a continuous harvest. Pick bush beans when the pods have reached full length, but the seeds inside have not yet filled out.
Common beans (Phaseolus vulgaris) including bush beans and pole beans typically self-pollinate and only need to be isolated by about 20 feet from other bean varieties in order to save pure seed. Note: favas, runner beans, and asparagus beans are not the same species, and require more isolation distance. To collect viable bean seeds, wait to harvest until the pods turn brown on the plants. In dry climates, beans can be left to dry completely on the plants, but if you live in an area with high humidity or a lot of rain during the late summer and fall when beans are maturing, it’s a good idea to bring the mature pods indoors to finish drying on screens or spread out in a single layer on newsprint. Most gardeners shell their saved beans out of the pods by hand, though they can also be threshed and winnowed in large batches. Make sure your beans have completely dried down before storing them in sealed containers in a dark, dry, and cool location.