The high-nitrogen activator should typically be about 10% of the composting materials. These are typically animal wastes – I have used real chicken crap, pelletised chicken crap, and clover. With the chicken manure each time I have scored a fail, whereas the clover was a success.
I suspect the trouble is that it’s hard to mix a concentrated activator properly. For starters it’s not pleasant to do, which discourages it being turned in right. The pelletised stuff is easy to distribute evenly, but even then it seems to lead to localised action.
The pellets seem to go white, like dog crap used to go white when left on the footpath in the 1970s. This leads to a fast and furious burn on the composting front, but with no staying power
The clover was more evenly spread – somehow I need to find a way of spreading the others more evenly. Or maybe go for the urine, preferably from carnivorous humans (there is more N in protein). In Ben Easey’s Practical Organic Gardening (Faber, 1955) he says dilute this with water 1:20 which should make for a better distribution. So I’m going to steer clear of using crap, because I am a wuss and don’t like dealing with it and it’s too concentrated anyway. Clover or urine will be my activators of choice 😉
Joanne’s note Oct 2016: We subsequently (in later heaps) used pelleted chicken manure mixed with water and stirred into a slurry. It took a lot of water to do this! Poor old Richard has a very sensitive sense of small (tough on a small farm with animals!) so he had to leave the rest of the team to finish up building the heap when we started to add the slurry…