If you have access to a lot of hair, you’re in luck.
Hair is high in nitrogen and has excellent water retention ability.
Before composting, hair can contain both heavy metals and chemicals from treatments.
However, multiple studies show that despite this the final result makes great compost. This may be partly down to the ability of the composting process to break down some toxic chemicals.
In many ways, composting hair is the same as any other technique. However, there are a couple of things to bear in mind.
Mix with both high nitrogen and high carbon materials
That sounds strange, as hair is already high in nitrogen.
However, hair is slow to break down in the composting process.
One study that did successfully make compost with large amounts of hair mixed it with both wood chips (which are high in carbon) and with food waste (which is high in nitrogen).
It’s likely that the hot composting conditions created by the correct Carbon: Nitrogen ratio is needed to break down the hair.
Indeed, a second study that looked at tannery hair found that the ideal temperature for composting hair was 40-50 Celsius, and the ideal C: N ratio was 35:1.
|How is hair broken down in compost?|
Hair is difficult to break down because is made up of a protein called keratin.
Fortunately, some bacteria produce an enzyme called keratinase, which breaks down keratin.
One review found that these enzymes work at a range of temperatures varying from 28–90°C.
Unless you are a commercial composter we always recommend keeping things simple – it’s virtually impossible to get exact C: N rates and temperatures.
Spread it throughout the heap
Hair can clump together. This reduces the amount of free air flowing through the compost.
Those excellent water retention qualities could also make it a wet mess if you have a lot of hair in one part of the compost.
To reduce the chance of this happening, spread the hair evenly throughout the compost and mix it well with other materials.
Aerate the compost well
Aerating the compost is always a good idea, as compost bacteria and microorganisms need oxygen to survive.
However, it becomes even more important with hair, as it is slow to break down. You can turn the compost to speed up the process or check out our guide to aerating compost.
Sift the compost
If you are concerned about hair remaining in the compost, you can also sift the compost to remove any hair from the final compost.
Do you need to chop up the hair?
I’ve got short hair, so I never need to worry about chopping up large strands.
However, if you have long hair to get rid off (and you have the time!) it might be worth cutting it down in size.
As we’ve seen, bacteria are responsible for degrading the keratin in hair, and they typically work better with smaller compost materials.
The Stafford Recipe
Both Rodale and Carry On Composting reference The Stafford Recipe for composting large amounts of hair. Here’s how to apply it:
- 10 pounds hair cut ¾ long,
- 20 pounds of cottonseed meal
- 11/2 yards of leaf mold.
- Mix the ingredients and add water.
- Turn regularly.
- The process should be completed after 30-60 days.
Hair is a great source of nutrients and has good water retention qualities, but it can be more challenging than some other ingredients.
It’s best mixed with both high nitrogen and high carbon ingredients and put through a hot composting process.
Still, I’ve composted my own hair clippings a number of times and never had a problem. I have found sheep wool to be more challenging, but even that fully degraded in time.