When it comes to fruit production, the goal of the gardener is to produce not only the best tasting fruit, but the largest and most succulent. When growing bananas (Musa acuminate), consider a few important factors to ensure you're growing the biggest fruit possible. Bananas require high humidity, warm temperatures found in U.S. Department of Agriculture plant hardiness zones 8b and 9, lots of water and a soil filled with nutrients. In order to grow larger banana fruit, you must tend to the plants daily to ensure all these conditions are met.
Select a type of banana that is known for its size. Not all varieties of bananas are created equal, and some varieties are known to grow larger than others. For example, "Cavendish" bananas are the type found in most grocery stores, and this type of banana produces large bunches of fruit.
Plant the banana tree in a dark, nutrient rich soil in order to yield the largest fruit. Use composted manure and organic mulch frequently to add nutrients to the soil, since the more nutrients the plant has, the larger bananas it will produce.
Water the banana trees twice a day. Banana trees require a significant amount of water because their large leaves evaporate water. Without adequate water, banana plants will produce small fruit. Many commercial banana growers water their plants two times per day using sprinkler systems.
Plant several banana trees together in a cluster to create natural protection from wind. When you plant several trees in close proximity to each other, this improves fruit production as the humidity between the plants is increased and the fruit itself is protected from the elements.
Fertilize the plants frequently, four to six times during the season, to yield the largest fruit. Apply 1/2 pound of 3-1-6 ratio fertilizer every two months. Apply 4 to 6 pounds of fertilizer when the bananas begin to produce fruit. This spike in fertilizer increases the size of the fruit produced.
Control the amount of suckers that form on the banana tree. By only letting a few suckers, or bunches, of bananas develop on the tree at a given time, more of the tree's nutrients will be fed to fruit which will improve the size.