SAN-SOIL project: new peat-free potting soil improvers from zero-miles olive mill waste recycling

Peat is widely used for potted plant production in nurseries and accounts for a significant portion (30-50%) of the growth media. Pistoia district accounts more than 5000 hectares of nursery farms which yearly use about 200000 m3 peatBecause of concerns about destruction of peat bogs, other organic materials have been investigated for their potential as substitutes for peat.From 2001 EC releases Ecolabel certification to only nursery farms that use peat-free growing media, promoting recycling of organic waste materials. Among them, compost shows good properties, especially when obtained from olive mill waste (OMW), whose disposal is of particular concern for potential soil and water-table pollution. SAN-SOIL project attempts to bring together the interests of local olive millers with those of nursery farmers, evaluating the production and use of compost from OMW used as peat surrogate in the preparation of growing media for potted plants. The experiments have been carried out at farm scale in Pistoia, involving 3 big nurseries and an olive mill in the production of 50 m3 of mature OMW compost tested in the production of 60000 potted plants belonging to 27 different species.SAN-SOIL aims at: 1) reduction of peat and fertilizer use in the nursery farms, with consequent saving of money; 2) reduction in the use of pesticides, thanks to the suppressiveness of OMW compost;3) higher environmental sustainability of both plant nursery and olive industry4) Ecolabel certification for peat-free nurseries 5) valuable zero-miles recycling of dangerous industrial waste streams, such as OMW.