Banana skins are nutrient-rich organic matter suitable for addition to a garden or houseplants. Banana skins contain two essential nutrients that benefit plants. The phosphorous and potassium contained in banana peels are important elements in root formation, blooming and fruit production.
Banana plants need large amounts of potassium to grow and produce bananas, but specialty potassium-rich fertilizers are expensive. An inexpensive way to give banana plants added potassium is to bury banana skins around the base of the plants. The phosphorous in the banana peels helps grow stronger roots so the banana plant can better utilize nutrients in the soil.
According to Reader's Digest online, there are two ways roses benefit from banana skins. The first benefit is that burying banana peels around the rose bush helps deter aphids. The second benefit is that as banana peels decompose, they release potassium and phosphorous into the soil to feed the rose bush and help it bloom.
It is not just an old wives' tale that if you put small pieces of banana skin into the cup of a bromeliad, it will bloom better. Bromeliads take in nutrients not only from their roots, but through the water in the cup of the plant. The phosphorous and potassium in banana peels feed the plant and encourage blooms.
Household dust clogs the pores of house plant leaves so they can not breathe. Use the inside of banana skins to clean and shine house plant leaves. Bury chopped banana peels in the soil to feed blooming houseplants. Do not use this method on plants with hairy leaves.