Community Composting at Stokes Wood Composting Demo Site

On this page we will be looking at the Community Composting at Stokes Wood Allotment Compost Demonstration Site in Leicester. This complements  the previous page, which looked at the display of compost bins on the site by recording  in greater detail the composting of organic materials left by plot holders to be composted in the Community Composting area. 

Almost by definition this is will not be  prime composting material, individual plot holders are likely to compost the  "good" and relatively easy items from their plots themselves and pass the more difficult items such as perennial weeds over to be composted on the communal site. This is part of the challenge.

We will be starting this page by looking at the material left in the two Reception bins and consider the effectiveness of the techniques used to deal with it.

Ideally when dealing with waste containing a significant proportion of perennial weeds the  weeds would be dried, drowned or hot composted. We are normally only on the site once a week so are unable to turn (aerate) the material in the bins as often as is required for quick hot composting e.g. every other day for the first few weeks, so we will see what happens.

The site Reception bins

The main area set aside for composting waste generated by plot holders who do not compost on their own plots consists of five open fronted pallet bins. We use open fronted bins to give easy access so that it is easier aerate the  organic material by turning it from one bin to another. Ideally for the first 18-21 days the material should be turned every other day, but we are only able to turn it once a week 

Two bins were designated  for the reception of waste as it was hoped that plot holders would separate the material into normal compostable waste, plant tops and leaves, annual weeds in one bin and perennial weeds in the other.  Experience on this site, and elsewhere, is that this will not happen, and we are already treating both Reception  bins the same  i.e. sorting through the waste and separating it into different types as the bins are emptied.

 

 

Working Pallet Compost bins

The reception and "working" pallet bins

First an explaination. This is a working site not and while I would like to Hot Compost ( Composting methods) the material submited from the allotment but this is not practical at this stage. We do not have enought material tomake a batch that will fill the compost bins. At present it will take about three weeks  and in order to make room in the Reception bins we are filling the actual wotking bin by adding material over three weeks so it will not be until after that time that we will be turning a full bin. 

Composting takes place more quickly if the material is cut into short lengths e.g. 1"-2" as this exposes a greater surface area to microbial action but this is not practical when dealing with  the type (mainly weeds with hardly any vegetable leaves) and amount of waste submitted. 

Ideally the  material being composted would be turned every two days to maintain a high temperature during its initial decomposition so as to kill pathogens and weeds and to compost the material quickly. As this is not practical on our site it is being turned weekly on  Wednesdays. It is hoped that this will maintain a higher temperature than would be reached without aeration to compost the material in a  three to six months  but it is unlikely to be hot enough to kill pathogens

The photographs below show the decomposition progress as the weeks progress.

  • Reception Bin A mixture of annual & perennial weeds, with soil left on the roots

  • "Working bin" 1 week 1

    Green waste layered with shredded paper at the start of the composting process.
    More will be added to the bin until it is full

  • Working bin 2 week 3 Temperature taken

    Material was turned from bin 1 into bin 2 in week 2 and has been left covered until week 3.
    Guess the temperature of this bin (answer at the end of the mornings work)

  • Week 3 Bin 2 Material turned back ti the empty bin 1

    Material is taken from the sides of the bin and placed in the what will be the middle of the new heap

  • Week 3

    The newly aerated heap starts to take shape

  • Week 3 More taken from the Reception bin

    During the week fresh material has been left in the Reception bins most of this will be incorporated into the working heap.

  • Week 3 The bin with fresh Greens and more Browns being added

  • Week 3 The bin is covered.

    The bin is now almost full. One more week should complete it.
    The carved head is only acting as a weight to hold the cover in place. It has no other significance.

  • Temperature before the week 3 mixing and additions

  • Week 4 Cover removed showing composting material. The material in the bin on the left will be added aonce the material has been turned into the unlined bin on the right

  • Week 4 Contents before turning

  • Week 4 Material from sides piled in the centre of the next bin

  • Week 4 Material from the centre of the bin turned material showing how well it is decomposing

  • Week 4 The material now turned into its new home

  • Week 4 Additional material from the Reception bin and shredded paper added.

  • Week 5 Cover removed and temperature recorded 40-45C depending on location

  • Temperature recording

  • Turning material, material from outer layers has been turned into next bin

  • Both bins

  • Turned material. No more material will be added but this will be turned again next week.

  • Close up of material showing stage of decomposition