Production of Organic Fertilizer from Rice Washing Water and Onion Peels

By: Marissa Ananias

I conducted as experiment to create liquid fertilizer using two main ingredients from kitchen waste: rice washing water and onion peels. The purpose of this experiment was to utilize household waste as a natural fertilizer that can nourish plants. The process of making this fertilizer is very simple, requires no cost, and is environmentally friendly.

Rice washing water and onion peels can be turned into liquid organic fertilizer through a fermentation process. During three days of fermentation, natural microorganisms work to break down the nutrients in these materials. Rice washing water contains starch and vitamins that are favored by microorganisms, while onion peels are rich in potassium and other essential nutrients that benefit plants. After three days, the mixture emits a slightly sour odor but not a rotten one. The fermented liquid can be diluted with water before being used to water plants. The fertilizer helps make the leaves appear greener, strengthens the roots, and improves sol fertility.

The first step I took was collecting rice washing water. Then I prepared a handful of shallot and garlic peels. I placed all the ingredients into a jar an added approximately one liter of rice washing water.

Tools and Materials

The jar containing the mixture was tightly closed and stored in a shaded area. During the fermentation process, I opened the lid briefly to release each day to release gas and stirred the mixture to ensure even fermentation. After three days, the water turned cloudy brown and had a mildly sour smell. This indicated that the fermentation process was successful

Fermentation Process (Three Days)

After the fermentation process was completed, I filtered the mixture to separate the liquid from the onion peel residue. The filtered liquid was then used as a liquid organic fertilizer. Before use, I diluted it with clean water at a ratio of 1:10 (one part fertilizer to ten parts water. This diluted fertilizer was then used to water the plants around my house.

I felt pleased because the experiment was successful. The plants watered with the liquid organic fertilizer made from rice washing water and onion peels appeared fresher and greener. Through this experiment, I learned that kitchen waste can be transformed into something useful and have a positive impact on the environment.

Filtering, Mixing, and Application of the Fertilizer