How Long Does it Take for Cardboard to Compost?

The Eco-Friendly Guide: How Long Does it Take for Cardboard to Compost?


Composting has become increasingly popular as people seek sustainable solutions for waste management. While most of us are aware that food scraps and yard trimmings can be composted, what about cardboard? In this blog post, we will delve into the world of cardboard composting and explore how long it takes for cardboard to break down naturally into nutrient-rich soil. So let’s get started!

What is Composting?

Before we dive into the specifics of cardboard composting, let’s briefly go over what composting actually means. Composting is a natural process where organic materials, such as kitchen scraps and yard waste, decompose and transform into nutrient-rich humus through the action of bacteria, fungi, worms, and other microorganisms.

Can Cardboard Be Composted?

Cardboard falls under the category of brown or carbon-rich material in composting. This type of material provides a source of carbon necessary for balancing nitrogen-rich green materials like food scraps or grass clippings. The good news is that yes, cardboard can indeed be added to your compost pile!

The Breakdown Process

Cardboard breakdown occurs in several stages during the composting process:

1. Moisture Absorption: Initially, when you add cardboard to your compost pile or bin along with other organic matter like leaves or vegetable peels; it absorbs moisture from its surroundings.

2. Softening: Over time, due to microbial activity within the pile alongside regular turning (mixing) which aerates the mixture; microorganisms start breaking down cellulose fibers present in the cardboard causing softening.


Shredded or torn pieces tend to break down faster than intact ones since they have more surface area available for microbial activity.

3. Decomposition: As the composting process continues, bacteria and fungi further break down the softened cardboard into smaller fragments.

4. Integration: The decomposed cardboard fibers blend with other organic matter in your compost pile, contributing to the overall nutrient-rich composition.

Factors Affecting Cardboard Composting Time

Several factors can influence how quickly cardboard breaks down in a compost pile:

1. Type of Cardboard: Thicker or wax-coated cardboards may take longer to decompose than thinner, non-coated varieties commonly used for packaging.

2. Size and Preparation: Larger pieces of cardboard will naturally take longer to break down than smaller ones. Pre-shredded or torn cardboard allows for quicker decomposition due to increased surface area exposure.

3. Moisture Levels: Adequate moisture is crucial for microbial activity; dry piles will slow down the decomposition process while overly wet conditions can lead to unpleasant odors or an anaerobic environment.

4. Temperature: Optimal composting temperature ranges between 120°F – 160°F (49°C – 71°C). Higher temperatures accelerate breakdown times compared to colder climates where decomposition may occur at a slower pace.

5. Frequency of Turning/Aeration: Regularly turning your compost pile helps provide oxygen necessary for aerobic decomposition, speeding up the overall breakdown process including that of cardboard components.

How Long Does It Take?

The time it takes for cardboard to fully compost varies based on different variables mentioned earlier; however, under ideal conditions, you can expect the complete breakdown within three months to two years.

Tips & Best Practices

To ensure successful and efficient cardboard composting:

1. Tear/Shred Cardboard: Break larger pieces into smaller bits before adding them to your pile as this increases their exposure surface area and promotes faster decomposition.

2. Layering: Alternate layers of green (nitrogen-rich) and brown (carbon-rich) materials including cardboard, striving for a 3:1 ratio. This balance promotes faster breakdown while creating nutrient-dense compost.

3. Moisture Monitoring: Regularly check your compost pile’s moisture levels to maintain the right balance as excessive dryness or wetness may hinder decomposition progress.

4. Patience is Key: Remember that composting is a natural process that takes time; don’t be discouraged if you don’t see instant results. Be patient, keep turning your pile regularly, and allow nature to take its course!


In conclusion, cardboard can absolutely become part of your composting routine! By following the tips provided above and being mindful of favorable conditions such as moisture levels, temperature, and regular turning; you’ll witness successful decomposition within months to years based on various factors involved. Embracing this eco-friendly practice not only reduces waste but also creates nutrient-rich soil for gardening or enhancing the overall health of our environment. So start incorporating cardboard into your compost today and contribute towards sustainable living!