India, 2023. A small bin stands in a lab, filled with organic waste.
But this is no ordinary compost bin. The compost is moving and shifting. Along the top crawl insects.
Welcome to the world of blatticomposting – a form of composting that could help deal with the mountain of organic waste countries like India are producing.
With the help of cockroach composting researcher Reddi Gowrisankar, who has made blatticomposting the focus of his PHD thesis, let’s explore the process of blatticomposting.
What is blatticomposting?
Blatticomposting is the process of turning fresh organic waste into a soil amendment with the help of cockroaches.
The soil amendment is often called compost, but the actual substance cockroaches excrete is called ‘Frass’.
The word blatticomposting comes from Blattodea, the scientific order of cockroaches.
The benefits of blatticomposting
As cockroaches are voracious and efficient eaters, they can process significant volumes of organic waste relatively quickly – making blatticomposting an ideal solution when there is little space.
‘Frass’ or roach poop is rich in nutrients essential for plant growth, including nitrogen, phosphorus, and potassium.
That’s not the only benefit. Cockroaches also contain anti-microbials in their digestive system, which helps kill germs. The result is a clean, hygienic compost that is less likely to carry pathogens.
Reddi told me that while Frass can improve over time, you don’t have to wait months before using it:
Want more out of blatticomposting?
Cockroaches are a good source of fat, protein and micro-nutrients, and can be used to feed animals – and even humans. While you probably won’t see them on your supermarket shelf soon, they also store well.
What cockroaches can you use for blatticomposting?
Not all cockroaches are suitable for blatticomposting.
For example, orange head roaches like it hot, and can’t be kept at room temperature. They also have an unfortunate tendency to eat each other, which as you can imagine doesn’t make them a great pet to keep in a container!
Ideal candidates for this blatticomposting can live in large, sociable groups, are unable to fly or climb smooth surfaces (so they can’t escape), and have a voracious appetite for a whole range of organic materials
Examples of roaches suitable for blatticomposting include the red runner cockroach (Nauphoeta cinerea), the Burrowing cockroach (Pycnoscelus surinamensis) and the Dubia cockroach (Blaptica dubia).
Researchers particularly like the Dubia as it breeds fast, and is easy to take care of.
Misconceptions around cockroach composting
Reddi Gowrisankar was keen to address some of the misconceptions around blatticomposting:
With the right type of roach and a properly managed cockroach setup, there is no danger of cockroaches escaping and causing an infestation.
Can you Blatticompost at home?
Reddi explained that the main barrier to composting with cockroaches at home is people’s disgust. (After briefly mentioning the prospect to family members, I can empathize with this!)
If you decide to go ahead with home cockroach composting, you need to select the right type of cockroach, set up an escape-proof composting container and then properly maintain it.
The container needs to be well-ventilated, and you need to create a substrate (bedding material). This can be made from materials like coconut coir, eggboxes, shredded paper. This substrate both provides the cockroaches with a place to hide and allows organic material to be buried, decreasing the risk of flies.
The container needs to be cleaned monthly – both to harvest the Frass and remove any uneaten food.
For a complete guide to composting with cockroaches, see the ebook Blatticomposting.
Blatticomposting v. vermiculture
I asked Reddi to imagine he had to choose between just two methods of composting – vermicomposting and blatticomposting. Which would he choose?
He pointed out that blatticomposting was only suitable for composting fresh kitchen and vegetable waste, while vermicomposting was better for semi-decomposed kitchen waste.
He also felt that vermicomposting beat blatticomposting in terms of speed and quality.
On the other hand, blatticomposting does have its pros – less moisture is required than for vermicomposting, which reduces the risk of mold growth and attracting other insects.
On balance, Reddi would choose vermicomposting – both because it is easier to manage than blatticomposting, and because worms (mostly!) don’t arouse the same feelings of disgust.
Just as with humanure, when you mention the idea of composting cockroaches to most people a look of disgust soon crosses their faces.
So while there are already small groups of enthusiasts, I can’t see blatticomposting taking off with home composters in a big way any time soon.
However, as a solution to some of the problems the world faces, blatticomposting holds a lot of promise.
It can help deal with the mountain of waste we produce, combat pathogens and help the soil – reducing the need for artificial fertilizers.
As such, it deserves its place in our arsenal of tools to combat waste and global warming.
Does frass need to be matured before use?
No, frass can be used right away. However, allowing it to mature might enhance nutrient availability.
What is the right moisture level for cockroaches?
Approximately 50%. Gowrisankar recommends monitoring for visible signs of moisture. A slight glistening on the substrate indicates adequate moisture levels. For this take a handful of the substrate and squeeze it lightly in your hand – it should feel moist but not release any water.
Chiarella K, Blatticomposting, Worman.com
Reddi, G., Sumithramma, N., Mulimani, V., Naveen, D.V., & Shambhavi, H.T. (2023). Comparative Evaluation of Compost Production with Burrowing Cockroach, Pycnoscelus Surinamensis and Earthworm, Eudrelus Eugeniae Using Different Types of Substrates and Its Quality Assessment. Journal of Experimental Zoology India, 26(2), p2181-2186.
Gowrisankar, R., Sumithramma, N., Mulimani, V., Pradhan, S.K., & Gundreddy, R. (2023). Blatticomposting: A Sustainable Approach for Organic Waste Management. International Journal of Environment and Climate Change, 13(9), 754-762. https://doi.org/10.9734/IJECC/2023/v13i930350