Poor worm farm ventilation will kill your worm farm

There are two important reasons for making sure that you have great worm farm ventilation.


The first of these is that worms needs oxygen to survive. Like all animals they breathe in oxygen and breathe out carbon dioxide. If the farm does not have sufficient air flowing through it then carbon dioxide will build up inside the farm and the worms will die.

One important characteristic of carbon dioxide is that it is heavier than air. This means that it will sink to the bottom of the worm farm where it stay and kill any worms. If you are farming in a windrows or other open systems then carbon dioxide is not an issue but if you are farming in closed containers, especially plastics, then it is.


If you are using closed containers as worm farms then you should provide ventilation by drilling or cutting holes in the bottom and sides of the container. Worms do not need a lot of oxygen so the holes in the sides do not need to be large. However rather drill too many than too few. The holes in the bottom of the container can be small,  ten or twenty 8 mm holes is adequate, these holes will allow the carbon dioxide to sink out of the farm and will allow air to circulate through.

It is important to cover the holes with some sort of agricultural fabric to stop the worms from escaping through.

Some commercially available plastic farms like the can o worms have hundreds of tiny holes in the top and bottom and ensure a good flow of air.

The other reason for ensuring that your worm farm has adequate ventilation is that anaerobic bacteria flourish in oxygen deprived environments. This means that if your farm does not have enough air flow, anaerobic bacteria will take over, heating up the farm and producing methane and other smelly gases. This process will kill your worms.

This becomes particularly important if you overfeed your worm farm; overfeeding leaves an excess of food in the farm which can rot and become anaerobic. Having adequate ventilation will help stop the process but if the farm is excessively overfed then it will inevitably become a super compost pile which will heat up and kill the worms.

The bedding material in your farm also has an important part to play in worm farm ventilation, good bedding material does not compact and allows air to flow freely through the farm.