Mature compost is the best fertilizer for the garden – and a natural and free one at that. But in order for organic waste to turn into beneficial substrate, the compost heap in your garden should be open at the bottom. Only then can earthworms and other invertebrates get in and aid the rotting process. Germany’s Agency for Renewable Resources (FNR) therefore advises against using containers that are closed at the bottom or covering the soil with stone slabs. A location in partial shade is also a good idea. The right mixture The agency recommends shredding larger waste before adding it to the c…