Global Compost Advocates Celebrate World Soil Day 2025,
Promoting “Healthy Soils for Healthy Cities”
Returning Organic Matter Back to Our Soils is Fundamental to Sustainability, Resiliency and a Positive Future for our Cities
Soil takes centre-stage on December 5th as soil and compost advocates around the world rally to celebrate World Soil Day 2025. Led by the Food and Agriculture Organization of the United Nations, this year’s theme, “Healthy Soils for Healthy Cities”, highlights the vital role soil plays in creating greener, more resilient and livable cities, improving public health and fighting climate change.
Soils are essential for life on Earth, intimately involved in nutrient cycling, greenhouse gas regulation and water cycles – making them baseline infrastructure for sustainability, both in our cities as well as rural communities. They serve as the planet’s largest terrestrial carbon pool and provide a home for approximately 59% of global biodiversity, underscoring their role as the living foundation of ecosystems. They also provide the foundational source for at least 95% of the world’s food, and yet, the FAO estimates that at least one-third of the world’s soil resources are already degraded with soil erosion threatening to reduce global crop production by up to 10% by 2050. This makes soil restoration a key priority for food security and climate resilience.
Jenny Grant, Head of Organics and Natural Capital said:
“Organics recycling as a key soil restoration practice is increasingly being recognized as an important means to regenerate soil vitality, close nutrient loops and support climate-resilient communities, it is something that everyone can and should be able to do – whether through home composting, community programs or city-wide initiatives. Every fruit or vegetable peel, fallen leaf and other organic residuals returned to our soils is an investment in healthier cities and a healthier planet. Sending these valuable resources to landfills or incinerators defeats this purpose – wasting nutrients, generating greenhouse gases and undermining the resilience of our communities.”
Soil is important for:
- Food security: Soils provide the foundation for at least 95% of the food we eat, supporting plant growth and providing the nutrients necessary for food, feed, fuel and fiber.
- Climate regulation: Soils are a major carbon sink, storing more carbon than the atmosphere and vegetation combined. They also play a role in regulating the climate and can mitigate floods.
- Ecosystem services: Soil, particularly peatlands, filter and store water, recycle nutrients and help regulate the global climate by storing carbon dioxide and other gases and preserving peat.
- Biodiversity and resources: Soils are a reservoir for minerals, water and air. There is an extraordinary diversity of organisms that call soil home – including bacteria, fungi, protozoa and nematodes, insects and earthworms – with many life-saving drugs originating from soil microbes.
- Sustainable development: Protecting soils is critical for achieving sustainable development goals, as soil degradation threatens food security, nutrition, and the ability to adapt to climate change.
Compost is an excellent source of organic matter, which provides a range of benefits to soil and its health, including its ability to support the growth of healthier food. It improves soil structure, increases water-holding capacity, reduces erosion and supports the growth of beneficial microorganisms. Compost also provides a slow-release source of nutrients to plants, which helps to reduce the need for chemical fertilizers and pesticides.
World Soil Day 5 December 2025
www.un.org/en/observances/world-soil-day; Home | World Soil Day | FAO
Globally organized by the FAO: Food and Agriculture Organization of the United Nations, World Soil Day (WSD) is held annually on 5 December as a means to focus attention on the importance of healthy soil and advocating for the sustainable management of soil resources.
The theme for 2025, “Healthy soils for healthy cities”, focuses on the role of soils in cities and the challenges posed by soil sealing and urbanization. Urban soils provide essential ecosystem services: they support food production, filter water, store carbon, regulate temperatures and sustain biodiversity. World Soil Day 2025 is a call to action. It invites policymakers, scientists, city leaders, civil society and citizens everywhere to reimagine urban spaces through their soils, ensuring that people and nature can thrive together in healthy green cities.
About the International Compost Alliance (ICA)
www.internationalcompostalliance.com
The purpose of the alliance is for organics recycling organizations around the world to work collaboratively to maximize the recycling of organic wastes and advance the manufacturing of certified, high-quality compost to benefit the environment, society and our members.
Currently, over 83 million tonnes of biowaste are recycled every year around the world. Not only does this recycle over 1 million tonnes of plant macro-nutrients, but, through storing carbon in soil and offsetting fertilizer use, it reduces greenhouse gas emissions by 9 million tonnes of carbon dioxide equivalents – an equivalent of driving an average car for 36 billion kilometers (23 billion miles); almost 95 thousand times the distance between the earth and the moon!
Despite our current success globally, our annual potential could be increased over 12-fold if all of the world’s unavoidable organic residuals were collected separately and composted.
The International Compost Alliance is comprised of:
The Australian Organics Recycling Association (AORA);
The Compost Council of Canada (CCC);
The European Compost Network (ECN);
The International Solid Waste Association (ISWA);
The Italian Composting and Biogas Association (CIC);
The Composting and Anaerobic Digestion Association of Ireland (CRÉ);
The Organics Recycling Association of South Africa (ORASA);
The Renewable Energy Association (REA);
The Waste Management Institute of New Zealand (WasteMINZ);
The United States Composting Council (USCC); and
The Compost Research & Education Foundation (CREF)