I add compost when I fork the soil over and can see there's not much compost left in the bed. For whatever reason, some of my beds have more bio-dynamic activity than others: the churning of worms and other soil denizens.
A couple years ago, as an experiment, I added shredded fall leaves (not leaf mold) to a few of my beds with a thin layer of compost on top of the leaves and straw mulch on top of that. I left these beds fallow and by late summer the leaves and compost were 85% broken down into the soil. These beds must have been a hot bed of action. lol
I find the addition of compost to be an on demand situation in my garden.
