Around 20% of the ufaFabriks generated waste, which is around 200 cubic meters per year, is compostable waste. Before the introduction of composting, the organic waste from the kitchens and the bakery, as well as leaves, grass and shrub cuttings and animal manure from the animals at the children’s farm where put into large heaps and left to rot. But the space these heaps occupied was needed to provide the ufaFabrik premises with required parking spaces and like this, the rotting process took about a year. This system did not provide ideal “working conditions” for the living organisms inside the heaps, since there was no ventilation inside, while the outside got too cold in winter and dried too quickly.
The organic waste is now composted in two compost tumblers with a capacity of about a cubic meter each. The greatest benefit these provide is that by constantly rotating, the compost it is always ventilated, there is a constant change of temperature and oxygen and the moisture level can be regulated. With this system, the rotting process can be completed within six to eight weeks in summer. After the rotting process is completed, the humus is used as a plant fertilizer, which is also for sale.
Bulky organic waste, like timber and tree branches are cut by a woodchipper. The mulch is used to keep flowerbeds and roads moist and light, or added to the compost tumblers as well.
Humus is also created by using a worm composting system. The worms transform the organic waste mixed with shredded paper to a high quality humus. Compared to other systems of composting, this takes a relatively long time and the worms need to be “fed” regularly. But taking good care of the worms proves worthwhile: not only do they produce very nutritious humus, the worms also loosen the soil and thereby provide good ventilation, which leads to a diversity of other organisms and bacteria in the soil. This helps plants to absorb more nutrients and facilitate their growth. Besides these benefits, the worm compost is also very effective when used to combat diseases like leaf blight.