The worlds best and worst compost

What is the world's best compost? If you Google this phrase you occasionally get diverted to various -e-books and calls to spend money on special recipes.

Most compost quality standards (eg UK PAS100) focus on ensuring the composting process has resulted in mature and stable compost. The bottom line - they measure if the material has broken down enough to be useful. So far so good...there is general acceptance that adding organic matter (compost) improves soils.

There a great deal of evidence from "soil science" that looks at the various parts of Soil Organic Matter (SOM). This science looks at the role of the organic part (compost that is still decaying) and the humic part (the part that is largely resistant to any further decay. The humic substance content has a profound influence on soil fertility and agricultural productivity - in simple terms the more humric substances the more fertile and productive your soil is.

There are no standards and no routine tests for how much humic content there is in compost. As this is the "vital" part, this is always a surprise to the HOTBIN team. This is probably due in part to the fact that testing for humic substances is expensive and difficult to do.

In our opinion, if you want to make the world's best compost - then you need to make compost that has a very high humic substance content. That is easier said than done. In our post 'is your compost good, bad or fabulous' we discuss wider aspects of compost quality and how to judge if what you are making is on the right track.

PS: the composting market is littered with offers to sell special powders, recipes and techniques to get 'more black gold' . Most flounder on the most basics principles of science and they all seem to lack that most basic part foundation of all science efficacy - people can repeat your method and get the same result. Ask for detailed scientific evidence before you buy!