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A compost

What is composting and what is it used for?

A natural fertilizer mitigating our ecological footprint

Recycling offers many alternatives to manage household organic waste more efficiently through techniques such as composting.

Biodegradable organic waste, also known as biowaste, represents approximately half of the content of the garbage bags generated every day in Spanish households. Thanks to composting, it's possible to recycle this waste to give it a new use or produce energy following the circular economy principles.

Optimization of waste management is at the heart of this new economic model, which is capable of combining efficiency and care for the environment. Within this cross-cutting strategy, composting is an excellent example of what we can do at an individual level to achieve this goal. In addition to recycling part of our household waste, this practice also enables us to reduce the amount of waste that ends up in landfills and mitigate our ecological footprint, which moves us towards a zero waste production model.

What is composting and what is it for?

Composting is a technique that results in the production of natural fertilizer produced from the decomposition of organic waste by bacteria, fungi, and animals such as worms, earthworms, and ants. This process also occurs in nature as a result of the biological oxidation of plant remains.

What kind of organic waste is used for composting? Most of the food waste we throw away every day can be composted: fruit and vegetable skins, fish bones, bones, egg shells, etc. Plant waste is also used such as pruning waste or smaller plant elements from gardening work. Used napkins and kitchen paper, sawdust, cork stoppers, and wood shavings are also suitable materials for this practice.

As a result, home composting will save your home or residential community money since you won't have to invest in fertilizers. At the environmental level, composting also brings important benefits, since by recycling organic waste, it reduces the amount of waste that goes to landfills or to final treatments such as incineration and, consequently, the emission of polluting gases such as methane and carbon dioxide.

Types of composting

A person adding to waste to a compost bin

Traditional composting

This type of compost is made using organic waste that is left to rest in piles that are turned regularly, either manually or mechanically, to oxygenate the mixture and prevent the compost from compacting.

A pile of food waste

Surface composting

With this composting method , known as static pile composting, you simplify the aforementioned process by applying the organic matter directly onto the soil. In this way, as it decomposes, nutrients leak directly into the soil.


An industrial compost

Industrial composting

This type requires more complex installations, including a forced ventilation system and temperature control to foster the development of more active bacteria that produce compost more quickly and avoid the appearance of germs.

Worms in a compost

Vermicompost or earthworm humus

This composting technique uses California red worms, a species capable of devouring virtually any plant debris. The resulting compost, known as worm castings or vermicompost, is known for its high nutritional properties.


A compost bin

Manure composting and poultry composting

Originally from Japan, this type of compost makes use of the remains derived from rice cultivation, adding water, molasses, crushed charcoal, yeast, and other elements to accelerate the decomposition.

What is compost used for?

Waste in a compost

These are some of its most common uses:
  • Compost is very rich in nutrients, making it a great natural fertilizer for your plants at home or to take care of gardens, green areas, or community gardens.
  • Similarly, composting can improve the fertility of agricultural soils, improve their water retention, and prevent erosion. Opting for compost as a fertilizer also reduces the use of chemical fertilizers without reducing the productivity of the agricultural land.
  • Due to its richness in nutrients, compost also makes it possible to recover degraded, barren, or contaminated soils, contributing to the preservation of the environment.
  • At the industrial level, compost generated from organic waste can be used to generate biogas, a clean and renewable energy source.

How to compost at home

As you will see below, composting at home is a really easy process to obtain a perfect natural fertilizer to take care of your plants or your community's gardens. Are you up for trying this technique of domestic recycling?


  1. If you are interested in making homemade compost, the first step is to get a composter. Nowadays, it's easy to find compost garbage cans at a very affordable price, but you can also make your own by reusing a fruit crate or wooden pallets. Ideally, the container should have a lid, so the temperature and humidity inside remain stable but allow air to enter since oxygen is essential for composting.
  2. Once you have your home composter ready, where do you place it? Experts recommend choosing a warm location, away from exposure to direct sunlight and protected from rain and wind.
  3. Now, you can start composting by pouring a first layer of dry waste such as garden soil, leaves, twigs, or sawdust.
  4. Next, add the organic waste on top of the previous base until it reaches a thickness approximately twice as thick as the dry layer. When this happens, pour another layer of dry waste and repeat the process again.
  5. This mixture should be stirred regularly to allow the organic matter to oxygenate.
  6. After that, all you have to do is wait! Home composting requires six to twelve months, depending on the type of waste and the technique used and the weather conditions.
  7. Are there odor problems? This is usually an indication that you have added some unsuitable material to the mix. Dairy, meat, or fish scraps or pet excrement, for example, are not suitable waste for composting.
  8. If you have followed these tips, the end result will be a dark-colored, soil-like homemade compost with a loose texture and a pleasant smell that's ready to be used.