MERRY CHRISTMAS TO EVERYONE, I HAVE A BANNA TREE GROWING IN MY YARD, THE LEAVES ARE TURNING VERY BROWN. I HAVE PUT IN THE GROUND PLANT FRUIT & CITRUS PLANT FOOD SPIKES A FEW MONTHS AGO. I CUT OFF A RM OF BANNAS ABOUT A MONT AGO, TYPE OF TREE IS A SMALL GROUP OF SWEET BANNAS AND OVER A MONTH AGO THE FRUIT HAS NOT TURNED YELLOW. WHAT IS THE PROBLEM, AM I TAKING THE FRUIT OF TO SOON. I LIVE IN MERRITT ISLAND FLORIDA.
Certified GKH Gardening Expert
Could you include a photo? This sounds like a fungal issue that was fed with nitrogen, which in large amounts will be toxic to the banana, and will allow infections in the soil to thrive.
This will need to recover at least a year before you feed this anything. When you do feed it, make sure it has more phosphorus and potassium than nitrogen.
Bananas are incredibly sensitive to infection, so you should never cut off dying leaves until they are bone dry. Only cut into dead dry material. Any green material cut will almost always get some sort of infection.
Apply Dolomitic Lime, and wettable sulfur to the area. Give this about a year to recover. Once the banana plant dies back to the ground, then cut it back and let it recover. Expect a year or two before it sets fruit again.
This article will give you more information on fertilizing bananas properly: https://www.gardeningknowhow.com/edible/fruits/banana/feeding-banana-plants.htm