Beans are one of the easiest vegetables to grow in the home garden. If you wish to maximize your space, choose pole beans over the bush variety. Pole beans make harvesting easy, take little garden space and need no help growing up supports. A number of snap-bean varieties are available for growing on a trellis, making it easy to find something that fits your family's needs.
Prepare your soil to be loose and rich. Add organic matter or a slow-release fertilizer. You need a sunny, well-draining area for most vegetables, including pole beans. Consider taking a sample of your soil to your local cooperative extension office for testing to determine the exact nutrients needed for amendment.
Place two poles or branches firmly into the ground using a rubber mallet, if needed, and tie tops together with twine by weaving twine around the sides, top and bottom of your cross section until secure. Repeat with other poles, placing each in a wide-bottom X shape (think teepee shape) no further than the length of your poles apart. Form two or more cross sections, depending on the desired length of your trellis. Face the trellis structure in a north-south position to allow for the most sunlight exposure.
Add a top pole running perpendicular to the ground for added support. Rest this pole in the cross-section of the X's and tie into place with the others.
Tie another pole perpendicular to the ground near the bottom of the south-facing side of your trellis, fitting each of your support X's into one structure. Be sure to secure it well to each support X.
Run twine between the two perpendicular poles on the south-facing side, continuing the length of the poles to create a "netting" place for your plants to grow. Space twine runners a few inches apart to allow for plenty of room for growth.
Plant pole bean seeds after the threat of frost has passed in your growing zone at the base of your trellis netting on the south-facing side by pushing beans just below the surface of the soil and covering lightly. Keep seeds 6-10 inches apart in hills or 3-4 inches apart in rows. When planting in hills, mound the dirt into a hill shape and plant three or four seeds in each hill; thin weaker seedlings once they emerge to allow for one or two plants. If growing in rows, create a trench with your hoe, plant bean seeds a few inches apart and cover lightly with soil. Thin seedlings once they emerge to 3-4 inches apart. Using hills or rows is simply a matter of preference.
Train seedlings to grow up the trellis, if needed, by wrapping emerging vines around the base of the trellis. The rapidly-growing pole bean will naturally begin to wind itself around anything it finds as it grows.