Don't toss or even compost your organic banana peels, but instead use them to fertilise your garden and boost the roots and flowers of your plants.
There are a couple of ways you can do it:
Chop the organic banana peel into small pieces and lay it around the base of your plants, preferably under the soil to reduce temptation for critters to carry it off.
Set your organic banana peels aside and let them blacken. When ready, whiz your organic banana peel in a food processor and sprinkle at the base of plants or just under the soil.
Bananas are rich in phosphorus which is an essential plant nutrient. Phosphorus aids photosynthesis, helps roots grow, and can also help gives plants bigger and healthier flowers - which is why rose growers love it so much.
Banana peel is also an excellent leather cleaner. Simply wipe the (inside) banana peel on your leather and then rub off with a damp cloth.
By the way, I am pretty sure the Banana skin teeth whitener tip is an urban myth.