Check the water content of my compost?

Tuesday, 4 February 2014  |  HOTBIN Composting

The right moisture level for composting is between 60-70%. Composting websites often suggest using the 'squeeze test'. Squeeze a handful of waste/compost tightly; a few drops of moisture should drip out. If the water floods out, it is too wet, none and it is too dry.

We find this test of little benefit and often results in excess water being added. At the start of the composting process, water in food and plants is stored inside the cells. As an example if you squeeze grass, it will not release water, however grass cuttings are 80% water and this has to be driven out of the heap.

There are a number of Excel type calculators that may help, but our belief is this is a level of detail beyond most users interest. Our mix ratio takes into account water in the majority of domestic materials – vegetable, food, green garden waste, prunings and grass waste. Keep to this and you will rarely be too far off. If your waste is too wet, the temperature will fall, and you will start to get a putrid odour – do not panic – just follow the advice in the wet and water logged compost.