How do Bacteria help my composting?

19 October 2012  |  HOTBIN Composting

Which bacteria work in the different temperature zones?

Bacterial activity within the HOTBIN causes heat to be released.

There are three key temperature zones within the HOTBIN; each zone houses its own type of bacteria. The bottom layer is the coolest layer followed by the warmer middle and finally the hotter, most active top layer. The types of bacteria and their preferred temperature zones can be found below.


Temperature range



50-70°F (10-21°C)

Start at lower temperatures and help to raise the temperature


70-140°F (21-40°C) 

Continue to generate heat and further raise the temperature

Thermophilic (hot)

+140°F (40-75°C)

Bacteria eat readily available and easy to consume sugars the first few days after a 'feed'.  When the ‘easy’ to digest food is gone, the bacteria population starts to decline and the temperature starts to fall. The temperature cycle starts again when new waste is added.

Mesophilic, cooling, lignin specialists


The more resilient parts of the waste are broken down, e.g. cellulose & lignin. Phase can last long time, but rarely is enough heat produced.