Mycelium is the network of all ‘threads’ of a fungus. These fungal threads are also called hyphae. Freshmushrooms grow kits are so far developed that the substrate consists of 100% mycelium. This soil is the ideal base for mushrooms to grow. Without fertilisation, this soil ensures several flushes. Therefore, it is important to harvest on time, before the spores of the mushroom fall on the soil.