Banana Peels for Nitrogen in Soil

N-P-K Defined

• A confusing array of fertilizers confront gardeners when selecting amendments for various projects. The most important components of all fertilizers are nitrogen, phosphorus and potassium. These are reflected in the three big numbers printed on a bag of fertilizer, which are known as its N-P-K analysis. The numbers represent percentages by weight of the three major nutrients required for healthy plant growth. The formulation a gardener selects depends on the needs of the specific plants they are growing. The N-P-K analysis of banana peels is 0-3.25-41.76, according to the Basic-Info-4-Organic-Fertilizers website. The third number means that nearly half its weight is potassium.

Nitrogen

• Nitrogen aids growing plants in producing chlorophyll, which interacts with the sun to help plants feed themselves through the process of photosynthesis. Nitrogen-rich ingredients in compost -- such as a blend of coffee grounds, fruit peels and vegetable scraps -- cause plants to flourish. Their nitrogen also helps the organic matter in a compost heap break down more quickly. It isn't necessary to seek an N-P-K analysis of homemade compost, but it is possible to obtain one through a university extension service. In general, adding a broad variety of kitchen scraps and yard debris to a compost heap creates a good soil amendment. It isn't problematic that banana peels contribute little nitrogen to the mix. They have other gifts to offer.

Phosphorus and Potassium

• The phosphorous in banana peels encourages root development and aids a plant's ability to flower and grow larger blossoms. Potassium also aids root growth. In contrast to phosphorus, it helps plants fight diseases and tolerate extremes, such as drought and winter cold. So a compost rich in well-rotted banana peels helps plants get established and protects their health. A quick experiment demonstrates the high potassium content of banana peels. Potassium can create violet-colored fireworks, according to online resource Chemistry Explained. Toss a banana peel into a bonfire and its will flash violet.

Carbon-to-Nitrogen Ratio

• Combined with other fruit and vegetable waste, banana peels become part of a an ideal mixture of carbon and nitrogen for speeding the decay of a compost heap. The more "juicy" the kitchen scraps, according to the University of Illinois, the higher their nitrogen. It says that a blend of fruit and vegetable scraps usually has a carbon-to-nitrogen ratio from about 25-to-1 to 30-to-1, which means that carbon-rich materials need to outnumber nitrogenous materials in compost. If there is too much nitrogen, compost becomes offensively smelly.