Do I Need to Add Bulking Agent?
Yes. Every time you add waste to your HOTBIN, you should also add the recommended amount of bulking agent and shredded paper. Together, they create the ideal conditions for fast, efficient hot composting.
Important: Do not use bulking agent as a base layer or empty the entire bag into the HOTBIN when setting it up. Bulking agent should be added gradually with each new batch of waste.
What Is Bulking Agent?
Bulking agent is simply a chipped woody material or natural mulch. Its purpose is to create and maintain tiny air spaces throughout the compost.
These air pockets allow oxygen to circulate freely, providing the beneficial aerobic bacteria with the oxygen they need to break down organic waste quickly and efficiently. Good airflow also helps prevent anaerobic conditions, which can cause unpleasant odors and slow composting.
How Much Bulking Agent Should I Add?
As a general guideline, add about one-fifth the volume of your waste in bulking agent.
For example:
- If you add 5 handfuls of kitchen scraps, add 1 handful of bulking agent.
- If you're using a kitchen caddy, fill it about 20% full with bulking agent after adding your waste.
These ratios provide a great starting point, but you can adjust them depending on the materials you're composting.
- Very wet materials (such as fresh grass clippings or food scraps) may require a little more bulking agent to maintain airflow.
- Dry, woody materials naturally create air spaces, so you may need slightly less.
Every HOTBIN is unique because every household generates different types of compostable waste.
Bulking Agent vs. Shredded Paper
Although they work together, bulking agent and shredded paper serve different purposes.
- Shredded paper helps absorb excess moisture and balance wet food waste.
- Bulking agent maintains airflow by creating air pockets throughout the compost.
Both are essential for maintaining the proper balance of moisture and oxygen that allows your HOTBIN to achieve fast, odor-free hot composting. They are not interchangeable.
