Ancient cultures have grown hydroponically for thousands of years. This type of growing system had a revived interest post-World War II when scientists and horticulturists experimented to find a way to grow crops in areas that do not have adequate arable land or no land at all for crops. The 1970s saw an interest in hydroponic gardening by commercial and home growers. Miniature and ultra dwarf fruit trees have been bred for container gardening, and many varieties do well in hydroponic grow systems as well. Miniature banana trees such as the Super Dwarf Cavendish do well in hydroponic systems such as nutrient film technique (NFT). They produce a small dessert banana. NFT kits can be purchased from your local garden center or from online dealers.
Purchase an NFT grow system. Look for systems that include net pots, aerator and water pump. Purchase a large table to hold your hydroponic grow system. Banana trees are heavy feeders, so purchase a grow medium (nutrient) specifically for tropical plants. Banana trees require at least 12 hours of sunlight, so you will need grow lights with a timer. Purchase rubber stall mats from a local feed store.
Select a location for your hydroponic system. Choose an area that receives direct sunlight and has little draft from windows, doors and air conditioners. Banana trees do not tolerate temperatures below 67 degrees.
Place rubber stall mats on the floor where you will set up your hydroponic grow system. This will keep the floor from becoming slippery with water. Set the table up on top of the mats. Install your NFT grow system according to the instructions included with your kit. Install grow lights over the hydroponic garden and set the timer to ensure 12 hours of daily light for your banana trees.
Plant the banana tree rhizomes into net pots that are included with the hydroponic grow system you purchased. You may need to have extra net pots depending on the number of trees you are growing.
Add grow medium to your grow system. Banana trees are heavy feeders, except when they are actively growing. Adjust the grow medium according to the growth cycle. During times of high growth use only 1/3 of the grow medium; all other times use it at full strength. Add grow medium weekly to your hydroponic system.
Clean your grow system regularly. Most systems require that the water in the system be completely changed every three weeks. This requires draining the water completely from the system, adding fresh water and grow medium
Harvest fruit by cutting the stalks. Indoor banana trees are ready for their first harvest in three to five years. Once your banana tree begins producing fruit regular harvests will provide a continual production of fruit.