The Composting Process

Composting is quite simply the aerobic decomposition of biodegradable material in a controlled environment.  For composting to take place we manage the presence of carbon, nitrogen, oxygen and water to optimise the rate at which naturally occurring micro-bacteria “bugs”, yeast and fungi break down organic materials to produce a stable “compost” (stable sanitised material).

Birch Airfield Composting Services

Waste Reception

The first part of our process is to ensure that the material we receive is suitable for composting.  All material coming into our site is first inspected to ensure it meets with our rigorous acceptance criteria, for more information on materials we can and cannot receive visit our Composting Services page.

Birch Airfield Composting Services

Batch Formation

To ensure the compost we manufacture is consistently of the highest quality we then shred and blend the input materials into long trapezoidal shaped heaps called “windrows”.  It is at this stage we make sure we have the perfect mix of carbon (woody material), nitrogen (grass clippings, fruit, vegetables, and herbaceous plants), water and oxygen (a structure that allows the air to circulate freely within the windrow).  Each windrow is allocated a batch number which allows us to trace input materials all the way through to the finished compost products.

Birch Airfield Composting Services


Throughout the composting process we carefully monitor the temperature and moisture within each batch to make sure the process is functioning optimally.  The “bugs” that break down the organic material naturally generate heat. We carefully manage this heat to ensure each windrow achieves sufficient temperature for sufficient time to kill any plant diseases or harmful bacteria that may have been present in the waste we are composting.  Windrows are turned periodically to make sure all material is subjected to these temperatures. We call this part of the process “sanitisation”.

Birch Airfield Composting Services


We continue to monitor each batch throughout the process to make sure the composting process has been completed.  When we see the level of activity from the “bugs” subside we know the compost is “stable” and ready for “screening” into finished products.



Once the composting process is complete we then use large mechanical sieves known as “screens” to grade the compost into different products.  We produce a range of products that are used by gardeners, landscape gardeners and local farmers to improve soil for growing plants.

Birch Airfield Composting Services

Once the finished compost is used by our customers the “recycling loop” is complete!

Birch Airfield Composting Services

Top of Page