The Spent mushroom compost means the remained soil without sporophores after the productive.period. The leftover can't be used for mushroom growing again (Gy6r1i, 2001). Unfortunately spent musnroom compost still has bad judgment, as it would be garbage, but on the contrary it is a significant and valuable material, which is full of organic residue, a perfect soil structure improver, nutrition supplement and propagating medium. In our experiment we took the following mediums: control material with 50% flat moor peat and 50% high moor peat (Novobalt) content, 100% spent compost, 50% spent compost and 50% control medium, 25% spent compost and 75% control medium. On the day of plantation and after the forcing experiment we took sample from the control medium  and from all mixtures.