Composting tips, advice and science.

A young woman standing by a her compost bin.

Study Finds the Sweet Spot for Turning Compost

05/04/24

If you’re a composter, you’ll already know that turning compost can speed up decomposition and improve nutrient quality by introducing oxygen.

It’s one reason the famous Berkeley method of composting involves turning compost every other or every third day.

But could there be such a thing as too much turning?

One study has put different turning schedules to the test to try and come up with the optimum frequency. 

Researchers in India set up two identical compost bins and tested how often turning affected decomposition. One bin was turned twice a week, while the other was turned once a week. 

Over 30 days, the scientists measured key composting factors including:

  • Temperature
  • Moisture levels
  • pH balance
  • Oxygen & organic carbon

The results

Hands holding dark compost from a grubby bucket.

  • Heat: The once-a-week bin reached the thermophilic (hot) phase faster and lasted longer—critical for breaking down waste and killing pathogens.
  • Moisture Retention: The once-a-week bin held slightly more moisture, preventing compost from drying out too quickly.
  • Nutrient Balance: Both bins produced high-quality compost, but more frequent turning didn’t improve the final product.
  • Oxygen Levels: Surprisingly, oxygen was higher in the weekly turned compost than in the bi-weekly bin. 

So how often should you turn your compost?

It’s worth remembering that this was a small study, and only compared a once a week turn with a twice weekly turn. 

However, it did strongly suggest that weekly turning will lead to a faster composting process, and that there’s no point in turning it more often. 

It’s also worth considering in the context of other studies which found that frequent turning reduced nutrient values and compost quantity.

But before you get out there with a compost fork and start turning even once a week, consider these two things:

1. Do you need optimum results?

Does it really matter if your compost is ready a little quicker? After all, even if you pile up organic waste and leave it, it will eventually turn into compost. It could be worth waiting a little longer for your compost if it stops you from putting your back out!

2. The researchers only researched one method of getting air into compost.

On CompostMagazine, we cover 11 ways to aerate compost, and only one involves turning. 

Final thoughts

Personally, and after much experimentation, my perfect balance between protecting my back and good results is a single turn with my pallet bin, and no turning with my insulated bin.

(With around a ton of compost in each pallet bin, it’s hard work!)

It’s true that I might wait a bit longer, but it doesn’t make any difference to my vegetable garden in the long run. 

If you want to find out the best compost turning frequency for your needs, see our complete guide to Compost Turning.

Source

Paron, O. (2024). The effect of turning on home composting. International Journal of Industrial Engineering, 11(3), 11-17. Central Institute of Technology, Assam, India.

We earn a commission if you make a purchase, at no additional cost to you.
02/15/2025 02:43 pm GMT