Beans can adapt to many conditions -- they are among the most widely grown vegetables in home gardens across the country -- but like most plants, they have an ideal range in which they thrive. Giving plants the sunlight, water and nutrients they need is essential to a healthy crop, and many bean plants have the additional need for support on which to grow.
Soil & Moisture
Beans grow best in soil that is moist but well-drained. In dry conditions, they need regular water, but excessive moisture can be detrimental. Do not water beans to the point where the soil cannot hold any more moisture. The soil itself should be loose, crumbly loam-type soil with a slightly acid pH between 5.8 and 6.3.
Applying mulch, compost or an all-purpose fertilizer just before planting is generally all beans need to thrive. A soil test can tell you if you have any specific mineral deficiencies that you need fix, but beans grow well in average fertile soil. Additional fertilizer after you have planted can actually be harmful; excessive nitrogen causes over-stimulated leaf growth, delayed flowering and a lower yield.
Sunlight & Temperature
Beans need ample sunlight to thrive, so be sure to choose a sunny location. They are frost-sensitive, so do not plant beans outdoors until all danger of frost has passed and the soil has warmed to about 55 degrees Fahrenheit. Average last spring frost dates are available from university extensions in most states.
Beans are available in pole and bush varieties. Bush beans do not need support, but pole beans are climbing vines that need poles, trellises or some other structure to climb on. Make a simple trellis by driving stakes into the ground every 3 or 4 feet with lengths of twine strung in-between. A trellis increases blooming in pole beans and makes them easier to harvest; just make sure your garden is laid out in such a way that the beans do not cast heavy shade on other plants for too much of the day.