Cover of the vlog from Youtube and Charles DowdingCredits: cover image by Youtube and Charles Dowding.

The following are my notes from the vlog "Three Types of Heap, see how they work and the compost they make"open in new window from Charles Dowding.

We could set the compost material it right on the ground but:

  • it wouldn't decompose as fast
  • it wouldn't get hot as it should
  • it will take more space.

So using a compost bin is a good choice.

What kind of bin and size?

A plastic modelopen in new window

Those that are square-shaped from the stores can hold up to 0.6 meter cube works better on the bare ground but it seems not to be enough to get efficient and hot enough (apparently max of 55°c).

You can get a good compost below those temperatures but the weed seeds will be able to sprout again.

To kill weed seeds, you need to get to 55°c or above.

It is, however, not very strong and plastic is a great conductor of heat so the temperatures can't get very high.

A pallet modelopen in new window

You just knock out the "feet" of the pallets. It allows you to save some space.

To assemble them easily, use a metal wire at the top and bottom. No screws.

It is a good idea to put cardboard under the bottom of each heap.

The model of pallet is not necessarily the EURPAL ones but the planks need to be close to each (about 5 cm max). This will help to keep the air flow to a minimum to keep the moisture and also help to keep everything inside the heap.

It is fine to put weeds (maybe not brambles 😉)

Using cardboard to cover the sides from inside.

So with three bins, for example

  • You fill the left one first
  • Then you start to fill the right one once the left is full.
  • When the left has shrunk half the size, you empty it into the middle one.
  • When the right bin is full, you start to fill out the left again.
  • When the right has shrunk half the size, you empty it into the middle one.
  • When the middle one is 5-6 months old or if the compost is ready, you can empty it and use the compost so that you can start to fill it again from the side bins.

A large wood structureopen in new window

It will cost more because of the amount of wood. But with a large size (1.5 meter cube), the heat goes much higher and therefore, the compost can be ready faster.

It takes 5 weeks to fill it with a 4000 m².

Within three months, however, the compost can be ready to use.

Charles uses a five-bin structure that obviously requires a lot of wood to build the structure...


  • Design a two-bin structure to quote it.
  • Find wood to recycle maybe

Some generic tips and facts

  • In winter, keep the compost out of the rain so it doesn't get too wet.
  • To kill weed seeds, you need to get to 55°c or above.
  • Keep the temperatures between 55°c and 70°c but not above to keep the fungal properties of the future compost.
  • To lower the temperatures, add brown material.
  • A compost should be moist but not too wet to be too smelly.

Thanks to Charles for sharing his knownledge.