Hydroponic gardens produce flowers and vegetables without soil, cradling the plants' root systems in an inorganic growing medium that is periodically flooded with nutrients in liquid form. Beans are excellent crops for the beginning hydroponic gardener because they are easy and quick to grow and require very little room, producing large quantities of food from even small systems. Beans come in two varieties, bush and pole, with the latter requiring a trellis.
Construct a simple ebb-and-flow system, if you do not have one already. Beans grow very well in this type of system. Drill 1/2-inch holes in the side of the bucket and the plastic tub, about one inch from the bottom, and connect with the plastic tubing, gluing into place. Cover the tubing that protrudes into the plastic tub with a piece of screen and secure it with a rubber band.
Add growing medium to within 1 inch of the top of the tub. Beans grow best in perlite or expanded clay pebbles.
Fill the bucket with nutrient solution and lift it higher than the tub. When the growing medium is flooded with nutrient solution, lower the bucket to allow the nutrient solution to drain out of the growing medium. Once your beans are planted, you will need to flood the growing medium with nutrient solution several times per day.
Plant seeds 1 inch deep, if you are starting your plants from seed. Bush beans should be planted 2 to 4 inches apart, and pole beans should be planted 4 to 6 inches apart.
Carefully rinse all soil from the roots of any transplants that you are moving into your hydroponic system. Dirt left on roots can introduce disease into the growing medium.
Insert a trellis into the growing medium, if you are growing pole beans. Seeds should germinate in three to eight days, and you should be able to pick your first beans in six to eight weeks.