I visit a lot of schools who like the idea of a compost bin and have one, but in terms of really using it, are a little unsure about what they are doing. The trick is to prepare in advance. Composting is not a spur-of-the-moment activity for a supply teacher. However with a little thought it makes a great project and practical activity for a class.
Firstly, whether you are a teacher, parent or interested person, try and download the Little Rotters Handbook. It has lots of clear information aimed at teachers who wish to introduce a compost system into their school. Sadly the Little Rotters website is no longer live.
Next, it’s perfectly possible to have a “leave it to rot” compost system. This is slow and can be prone to going a little wonky. It’s important to have a mixture of fruit and vegetable peelings going into the bin alongside scrunched up paper and dead plant material such as stalks and stems. Have 3 compost bins going at once. The first bin is filled in term 1, the second in term 2, the third in term 3. Leave the compost in each bin for a year to break down before using. Remember to turn it occasionally or poke it with a stick to keep it aerated.
At home I have 2 systems happening at once. Firstly I have my “dump it” compost bin. This is where I chuck my fruit and vegetable peelings along with a bit of cardboard, weeds and other compostable matter. Some gardening books will warn you not to add perennial weeds as they will simply grow again from the compost made. Because I tend to use mulch this doesn’t especially bother me.
Straw that was part of a postal delivery of some child-size gardening tools.
Below is the “hot composting” system at Inverary Primary School. The janitor is a keen gardener and oversees this operation. Basically it’s not dissimilar to the layering system, except the compost is turned more easily in these containers.
Again, to have a hot composting process, there needs to be a storage system for waste material so that it can be added in the correct mix and quantities. Inveraray Primary School have a whole shed dedicated to this! Wow!
Below, is an example of a keyhole composting system from the Cruikshank Botanic Garden in Aberdeen. The name comes from the design. If you look at the brickwork, there is is a gap which allows you to walk into the centre of the feature and deposit your waste matter into the central compost ‘bin’. As the waste matter breaks down, nutrients and water feed the surrounding raised bed where vegetables can be planted. Lots more information can be found online about this compact method which is common in arid countries but increasingly becoming popular everywhere as it can be made entirely from recycling materials such as old bricks and rocks to create the design.
In the corner of the Saules Gojus school in Lithuania, I saw another different approach. The garden waste and vegetables and fruit are put in one dark corner of the grounds. Everything is left to rot down. Melons are planted here every spring so that the compost heap becomes an informal raised bed.
As with most outdoor and gardening matters, trial and error is an important part of the process. It’s a matter of finding the right composting container and system that suits your own and the children’s needs within the climate and setting that you live and work.