Well, sometimes you should dig your compost in – like when you are starting a new garden bed, building a raised bed from scratch, or working with vegetables, such as potatoes, where you have no choice but to disturb the soil. However, as a rule, it is better to disturb the soil as little as possible, so you should generally add your compost as a top-dressing. Why is this?

 

Soils are living ecosystems, with millions of invisible organisms in every handful of healthy soil. These organisms, like us, prefer to live in organized communities, with stable structures (much like our towns and cities). They spend a lot of energy building these communities, which in turn are the foundation for good soil structure. This structure, which includes stable soil aggregates and pore spaces, allows water and air to infiltrate. A well-structured soil is the key to natural fertility, drought resistance, and pest and disease suppression.

 

When we till, dig, hoe, or otherwise disturb the soil, we become “home wreckers”, forces of destruction that tear up their carefully constructed communities. This destruction forces the microbes to spend much of their energy re-building, instead of helping our flowers or crops to grow. Compost, on the other hand, provides these beneficial microbes with the food energy they need to build and maintain soil structure. So, if you have to dig, dig in compost. If you don’t have to dig, top dress with compost. In this way, you can always take pride in being a home builder, rather than a home wrecker.