A substrate intended to be used as a culture support, characterized: • on the one hand, in that it comprises: - a first portion, of the substrate forming the skeleton of the substrate and representing more than 70% of the total volume of said substrate, consisting of particles P >100μm with a grain size greater than 100 μm, the whole of said particles consisting of hard particles P D>100 and of cork particles P R>100, said cork particles making up a volume proportion PV comprised between 5% and 90% by volume of this first portion; - a second portion of corpuscle elements P <100 with a grain size of less than 100μm, and making up from 0 to 450g/L of said substrate; - a third portion, making up from 0 to 200g/L of said substrate, consisting of thin fibers with a length comprised between 3 mm and 100 mm and with a diameter comprised between 5 μm and 35 μm; - a fourth portion, making up from 0 to 200g/L of said substrate, consisting of elongated and/or surface inclusions, each of these elongated or surface inclusions having at least one of its dimensions considerably greater than the grain size of the particles of the first portion, • on the other hand, in that the sum of the dosages of the third portion and of the fourth portion is less than 1 g/L of said substrate. • on the one hand, in that it comprises: - a first portion, of the substrate forming the skeleton of the substrate and representing more than 70% of the total volume of said substrate, consisting of particles P >100μm with a grain size greater than 100 μm, the whole of said particles consisting of hard particles P D>100 and of cork particles P R>100, said cork particles making up a volume proportion PV comprised between 5% and 90% by volume of this first portion; - a second portion of corpuscle elements P <100 with a grain size of less than 100μm, and making up from 0 to 450g/L of said substrate; - a third portion, making up from 0 to 200g/L of said substrate, consisting of thin fibers with a length comprised between 3 mm and 100 mm and with a diameter comprised between 5 μm and 35 μm; - a fourth portion, making up from 0 to 200g/L of said substrate, consisting of elongated and/or surface inclusions, each of these elongated or surface inclusions having at least one of its dimensions considerably greater than the grain size of the particles of the first portion, - a first portion, of the substrate forming the skeleton of the substrate and representing more than 70% of the total volume of said substrate, consisting of particles P >100μm with a grain size greater than 100 μm, the whole of said particles consisting of hard particles P D>100 and of cork particles P R>100, said cork particles making up a volume proportion PV comprised between 5% and 90% by volume of this first portion; - a second portion of corpuscle elements P <100 with a grain size of less than 100μm, and making up from 0 to 450g/L of said substrate; - a third portion, making up from 0 to 200g/L of said substrate, consisting of thin fibers with a length comprised between 3 mm and 100 mm and with a diameter comprised between 5 μm and 35 μm; - a fourth portion, making up from 0 to 200g/L of said substrate, consisting of elongated and/or surface inclusions, each of these elongated or surface inclusions having at least one of its dimensions considerably greater than the grain size of the particles of the first portion, • on the other hand, in that the sum of the dosages of the third portion and of the fourth portion is less than 1 g/L of said substrate.