Household waste refers to the waste generated from homes, particularly from the kitchen and other household activities. Although our household waste may seem insignificant on its own, when combined with the waste produced by thousands of other homes, it becomes an endless source of waste.

According to data from the Ministry of Environment and Forestry (KLHK), throughout 2023 there will be around 19.56 million tons of waste produced in 96 districts/cities in Indonesia. From the same data, it was revealed that 39.1% of waste came from households. To reduce waste, one way to manage household waste is by using a composter at home.

Definition of Composter

Composting is the process of recycling organic materials, such as leaves and food waste, into compost which is useful for fertilizing soil and plants. In nature, the compost process is aided by microorganisms like bacteria, fungi, and actinomycetes. However, by using appropriate tools and materials, we can accelerate this process.

Composters have many benefits, such as:

• Reduce the amount of waste thrown into landfills.
• Producing nutritious organic fertilizer for plants.
• Improve soil quality and plant fertility.
• Supporting a more sustainable lifestyle.

Before starting the composting process, it's important to understand the various materials and types of composters that can improve the composting process and results.

Compost Ingredients

To create compost, we require four essential components: Carbon, Nitrogen, Water, and Oxygen. Carbon can be sourced from brown waste items such as dry leaves, sawdust, wood shavings, corn husks, straw, and paper waste. Meanwhile, Nitrogen can be obtained from green waste sources such as vegetable or fruit scraps, fresh leaves, tea, coffee, and eggshells.

For optimal results, make compost by mixing brown and green waste in a 3:1 ratio. Brown waste can also be made into compost, but it takes more time. Besides the materials mentioned above, some materials should not be included in the composter.

Some materials that should not be put into the composter are:

• Meat, bones, fat, and milk.
• Dog feces and cat feces.
• Weed plants that are pests or affected by pests.

The materials listed above can hinder the decomposition process in the composter. Additionally, these materials may attract animals, like flies, which can cause maggots to appear during composting and lead to the spread of disease. Once the materials have been sorted and selected, they can be processed using any of the available types of composters.

Types of Composters

1. Takakura

The Takakura method is a technique for processing organic waste that was developed by Koji Takakura, an applied chemist from the Himeji Institute of Technology in Japan.  It has gained popularity among the public since 2004 due to its simplicity. To create this composter, we can use a basket or container with holes lined with used cardboard. The holes in the container function to maintain air circulation in the compost, while the cardboard serves as a base and regulates the humidity of the compost.

2. Pottery Pot Composter

This type of composter takes inspiration from local Indonesian wisdom, where people make holes in the ground to bury waste. The choice of earthenware material is not arbitrary, as it has cavities that provide better air circulation compared to plastic containers.

3. Drum or Container Composter

This composter is ideal for indoor use and is often preferred by those with limited space. To create it, we can use an old plastic or metal drum that has been perforated at the bottom to get air circulation.

4. Worm Bin

Another type of indoor-friendly composter. As the name suggests, this composter relies on worms as decomposers. Use a plastic box with a lid as a container for compost and worms.

5. Biopore

Biopori holes are a type of composter that is stored in the ground. These composters can accommodate all types of organic material, including leftover meat and bones. Biopori is created by planting a 10 cm diameter PVC pipe that has been cut into small holes in the ground to a depth of 1 meter.

How to Make a Simple Composter

Now that we know the materials and types of composters, let's try making a simple composter! All types of composters have almost the same basic manufacturing method, except for biopores, where the compost material does not need to be stirred. Here are 5 easy steps to make a simple composter at home.

1. Prepare compost materials such as brown waste, green waste, soil, and rice washing water. You can also add EM4 as a bioactivator to speed up the decomposition process. After that, prepare tools according to the type of composter.

• Takakura: basket with holes, used cardboard
• Pottery: earthenware pot
• Drum or container: used plastic/metal drum
• Biopori: PVC pip.

2. Make a hole in the composter container with a drill and add a mixture of green and brown waste in a 1:1 ratio. To make the decomposition process easier, you can also chop the green waste first. After mixing, add soil in a 1:1 ratio, which will help the composting process.

3. Put the mixture into the compost bin. Sprinkle brown sugar water or rice wash on it until it looks slightly damp, then close the compost tub tightly.

4. Stir the composter once a week, except for the Biopori composter. In the first and second weeks, microbes will start to decompose the waste and the compost temperature can reach 40°C.

5. Usually, the composting process takes around 4-6 weeks. The finished compost will be black and will not emit a garbage smell. The fine part can be used straight away, while the coarse compost can be mixed back into the compost bin as an activator.

It's easy enough to practice at home, right? Let's start processing household waste with a simple composter to reduce the endless waste problem!