What are compost accelerators (or activators) and do you need to add them in composting?
You do not need to add commercial compost accelerators when HOTBIN composting. Save your money – there are plenty of FREE, natural compost accelerators.
Most commercial accelerators (or activators) do not list what they contain (Buyer beware!). We have researched them and found they mainly contain ground up plant, seaweed or dried blood with a small amount of enzymes and or bacteria culture.
Here’s our issue: bacteria produce the enzymes they need. If your waste has no bacteria – grab a handful of soil and sprinkle it in your compost bin – hey presto billions of bacteria in your waste. That just leaves the ground up food waste.
How much ‘ground up’ food are you adding and at what cost?
A packet of compost accelerator (activator) typically contains 0.5-1Kg and costs £5-10, so that’s around £10/kg for your ‘bacteria food’. Would you add a bag of sugar to your compost bin? No – well sugar only costs £1.50/Kg so about ten times cheaper. Normally you add about 10-20g of activator each time you use it. When you add a kitchen caddy of food waste into the bin, you add around 3Kg of bacteria food for free. Our point: you are adding extraordinarily expensive and unnecessary ‘bacteria food’. If you want to learn more or check out what some of the branded activators contain see our detailed accelerator post.
How do I get my compost heap to work faster?
The main reason for thinking about adding activators is to get the waste to break down faster. You will achieve faster composting by retaining heat – composting is 32 times faster at 60C than it is at 10C. If your heap is struggling to get to a high temperature (40-60C), here are some low cost “accelerator” alternatives:
- Fresh grass mowings are an excellent natural accelerator
It works because the grass is easy for bacteria to digest (high cellulose, low lignin, high nitrogen) and the pieces are thin (hence high surface area. You also have a lot of it. Mixed in, grass will “accelerate” stubborn heaps to 70°C within a few hours.
- Fill the bottle (provided) with boiling water to “kick start”
This costs approx 10p/use is fast, cheap and effective. (Only works in an insulated bin like the HOTBIN). It works because food availability and particle size are not the main reason the heap is not heating up. Bacteria will eat food and grow quickly – but the rate at which this occurs is temperature dependent (see Q10). At 0°C there is almost no growth (no matter how much food you add, the bacteria will not grow and produce heat). At 70°C they ‘work’ 64 times faster than at 10°C. Even a short input of heat is enough to get the bacteria through the “temperature lag”.
- Add 2 hands full of chicken pellets (Buy a 10Kg bucket)
Pelleted chicken poo is high nitrogen content and easy for bacteria to digest so you get a fast release of heat. One or two hands full is enough to raise the temperature of stubborn “brown” materials (e.g. leaves). OK this is still buying – but is economical compared to other activators!
- Dried blood
As per chicken poop, but it tends to be more expensive.
Post by HOTBIN composting. The hot composter bin that does what it says: rich compost, fast, all year round.