What Can You Put Into A Composter?

Composting is a cost-effective and eco-friendly method for managing household waste. A significant portion of what we typically discard—such as food scraps and yard trimmings—can actually serve as valuable composting materials. Through this natural process, organic waste is transformed into nutrient-rich compost, a high-quality fertilizer that can be used in gardens, farms, and landscaping projects.

While many people assume composting is as simple as tossing green and brown kitchen waste into a pile and letting nature take its course, successful composting requires a basic understanding of what to include—and what to avoid. Choosing the right balance of materials ensures proper decomposition, reduces odors, and results in high-quality compost.

What Is Composting?

Composting is a process of converting organic waste into organic fertiliser by controlling temperature, humidity and oxygen supply to promote the growth and activity of micro-organisms that break down organic matter into more stable organic matter. The following is the composting process.

Microbial decomposition: the main process of composting is the decomposition by microorganisms. These microorganisms include bacteria, fungi and other microorganisms that break down organic matter under suitable environmental conditions.

Thermal Fermentation: During the composting process, the decomposition of organic matter releases energy, resulting in an increase in temperature. High temperatures help kill pathogens and weed seeds and promote rapid decomposition of organic matter.

Humidity and Oxygen Regulation: Compost piles require proper humidity and oxygen supply to support microbial growth and activity. Too much or too little humidity can affect the rate of decomposition, while too little oxygen can cause the compost to produce a bad odour and slow down the rate of decomposition.

Conversion of organic matter: Organic waste is gradually converted into more stable organic matter during the composting process, eventually forming a mature organic fertiliser that is rich in organic matter, trace elements and nutrients that are beneficial to plant growth.

List of Items That Should And Should Not Be Composted

Note: Although some foods can theoretically decompose, placing them in the compost pile may attract pests or create odours, so it's best not to place them directly in the compost. Some foods that are prone to odour require the use of an electric composter to generate pre-composted material.

How to Deal With Food That is Not Suitable for Composting？

Foods that are not suitable for composting usually include animal products (e.g. meat, fish, eggshells), dairy products (e.g. cheese, milk), edible oils and fats, sweets and desserts. These foods are prone to causing odours, attracting pests or producing harmful bacteria in the compost heap, so it is not recommended to put them directly into the compost heap.

Specialist disposal sites: Some areas offer specialised waste disposal services. These units usually adopt more environmentally friendly and safer ways to dispose of such unsuitable food waste.

Reduce food waste: The best way to deal with food waste is to minimise it and avoid generating large quantities of food that is not suitable for composting. The generation of unsuitable food for composting can be effectively minimised through rational planning of food purchases and storage, as well as rational use of surplus food.

Using an electric composter: Electric composters can pre-treat animal products (e.g. meat, fish, eggshells), dairy products (e.g. cheese, milk) and other foods that are not suitable for direct composting. Food waste is processed into pre-composted material through heating, grinding and sterilisation. Re-introduction into the composting area for microbial decomposition reduces pest attraction and odour emission.