You don’t need artificial fruit ripeness for bananas to ripen this season. Your bananas will ripen very quickly because of the heat. If you pick the bananas when they are mature and ready, they will quickly ripen if you store the bunches in a dark place, such as a box or empty mealie meal sack. If you want instant results, put a few ripe oranges or lemons in the box or a sack of bananas. Ripe fruits naturally produce Ethylene (Ethylene fruit-ripening hormone), which may help in the winter when banana maturity and ripening are relatively slower.
The colour and flavour of your bananas depend on the variety you are growing. The degree of yellowing of the fruits may vary for different varieties. Other varieties may have different colours when ripe; such bananas won’t turn yellow even with artificial ripeners (Ethylene fruit-ripening hormone).
Black spots on bananas are bruises from rough handling during picking or storing the unripe bananas. The unattractive blackening from bruises is why commercial growers handle them in water ponds to minimize physical impact.
If the bananas are not getting ripe but start rotting, they are too immature and need more time on the plant. Commonly, the plant falls before the bunch is ready, or it is picked too early. Allow at least one banana to turn yellow before harvesting the banana bunch. If bananas are not mature enough, they may spoil with black spots, poor texture, and flavour rather than ripening.