A single crystal is pulled by the FZ method, in which in a first phase, a lower end of the polycrystal is melted by the melting apparatus, in a second phase, a monocrystalline seed is attached to the lower end of the polycrystal, and in a third phase, between a lower section of the seed and the polycrystal, a thin neck section is formed whose diameter is smaller than that of the seed, where the power of the melting apparatus before the third phase is dynamically adapted in dependence on a position of a lower phase boundary (PU) between liquid material and solid material on the part of the seed, and where the power of the melting apparatus during the third phase is dynamically adapted in dependence on the position of an upper phase boundary (PO) between liquid material and solid material on the part of the polycrystal plant.