Case Study – Redbricks composting

The Redbricks Estate has a long history of encouraging recycling and composting. The large recycling initiative Emerge recycling was founded from a flat on the estate. There are many compost bins in the communal gardens on the estate. However, when Green Zone started, the level of compost and the general ‘state of the bins’ being produced was quite poor. Some of the pallet larger bins had either been removed because of vermin problems or were inactive because of an inappropriate mix of materials and inattention.

 I think it has made people aware of the green spaces in the Redbricks and hopefully
made them appreciate them more. I think people know a lot more about how to make
compost than they did before, too.”
resident survey response

Circular Wire mesh leaf mould bin

Before the Green Zone project started, the Greening the Redbricks group brought in new rat-proof tumbler bins called mulch makers with ‘community benefit’ money donated by ‘Bramhall construction’ the contractors carrying out the large scale kitchen and bathroom replacement scheme on the estate. These have helped attract new people to compost their food waste. Based on positive feedback about these during the project, the Green Zone purchased more, larger-scale composters for other locations. This has also combined with more gardening activity so that garden waste can be mixed in with food waste to create the right mix of materials needed for good composting.

Rob, one of the Redbricks residents, had previously worked for a composting firm and offered to do a composting project to try to increase the level of composting on the estate further. The project consisted of the following elements:

  1.  A composting workshop
  2.  A composting survey to find out current habits and attitudes
  3.  A composting report to analyse results from the survey
  4.  Research and suggested solutions and locations of new composting facilities
  5.  Installing new composting facilities and information and education to encourage use

Copies of the survey, report and suggested solutions are available on the online toolkit and in the appendix.  It encouraged the widespread use of wire mesh bins for fallen leaves to create leaf mould as there are no problems there with people adding cooked food by mistake. The research into the different market solutions for composting also suggested the following products, which seemed to be most suitable to our estate where vermin problems are of concern to people. Because our project had some funding available for this area, we were able to purchase the mulch makers. However, it is possible to rat-proof your compost bins in other ways, with wire mesh and normal council compost bins.

Making simple garden compost

Composting kitchen waste used to be commonplace and is a really important way to cut emissions of methane from landfill sites. Even if people don’t have time to work in the garden, many would be happy to see their vegetable peel turned into a lovely rich hummus.

You need a site that’s at least 1 m by 1 m and a container (see below). Start by spreading a layer that is several inches thick of coarse, dry brown stuff, such as leaves, twigs or old newspapers, and top that with several inches of green stuff (grass or plant cuttings). Add a thin layer of soil. Add a layer of brown stuff.

Keep layering the compost heap in the same way and every couple of weeks use a garden fork or shovel to turn the pile. If you turn the pile every couple of weeks and keep it moist, you will begin to see earthworms throughout the pile and the centre of the pile will turn into black, crumbly, sweet smelling soil. When you have enough finished compost in the pile to use in your garden, shovel out the finished compost and start your next pile with any material that hadn’t fully decomposed in the previous one.

“I think the compost bins are great!”
Resident survey response

Building a compost bin

Many councils will provide free bins but it’s also easy
enough to build your own. Wire mesh compost bins are versatile, inexpensive and easy to construct. A circular wire mesh bin may be made from poultry wire, hardware cloth or heavy wire mesh. Four wooden pallets can also be hinged or wired together to construct a compost bin. The bin should be constructed with at least one removable side so that materials can be turned easily.

Composting Trouble shooting

Rotten odour means there is not enough air and the pile is too wet. Try turning pile, adding coarse, dry materials (straw, corn stalks, etc.). Ammonia odour means there are too many greens (excessive nitrogen/lack of carbon). Add browns (straw, paper or sawdust).

Rats can identify cooked food in compost bins or it may be too dry and used as a nest. If you have flies in the compost, this is due to uncovered food or other nitrogen-rich stuff. Cover it with browns or stir.

If activity in the compost has stopped this could be due to various causes:

  1.  Too much carbon (browns) in the material (leaves, cardboard etc). Add green, nitrogen-rich material like green vegetation, grass or kitchen scraps.
  2.  Compost contains material that is too coarse, such as twigs, so it becomes too airy and dry. Remove this material and get rid of it or chop it up finely and mix back in.
  3.  There is too little material in the compost for the micro-organisms to work on. Add more material to the heap, maintaining the carbon/ nitrogen balance.
  4.  The compost is too compacted and the air cannot get in. Stir properly and, if necessary, add finely chopped twigs or other coarse material.
  5.  The compost is too dry. Water carefully and stir thoroughly. It should be no wetter than a damp bath sponge.
  6.  The compost is too cold. When the weather is cold it is important to add new waste materials as often as possible – preferably every day- and to keep the compost properly aerated. You may be able to wrap some insulation around your heap too.

(Adapted from Composting for All website by Nicky Scott).

Green Johannas

Green Johanna Composter in situ in Leaf St

Green Johannas are simple to use and superficially similar to the standard ‘dalek’ type of compost bin. However, improved design ensures they are rat-proof whilst still allowing access for beneficial worms and microorganisms. They allow enough air circulation to ensure, with correct use, ‘hot’ composting bacteria to work – this is what enables the composter to safely break down cooked food, meat fish and dairy. Capacity – no exact capacity given, but designed to accommodate the waste from an average family (7.4 litres per week). They cost around £100.

Jorakompost JK series horizontal tumblers

These are dual-chamber rotating tumblers, which rotate around the horizontal axis. Food waste is deposited into one chamber until it is full, then that chamber is shut and left to finish composting whilst the other is filled. Once the second chamber is full, the first is emptied and that can then be re-filled. This allows for continuous composting activity rather than having to periodically empty then restart a traditional compost bin. Again, these are designed to be rodent proof and allow for ‘hot’ composting to break down meat, fish and dairy.