  The bulk helimagnet Cu2OSeO3 represents a unique example in the family of B20
cubic helimagnets exhibiting a tilted spiral and skyrmion phase at low
temperatures when the magnetic field is applied along the easy <001>
crystallographic direction. Here we present a systematic study of the stability
and ordering of these low temperature magnetic states. We focus our attention
on the temperature and field dependencies of the tilted spiral state that we
observe persisting up to above T =35 K, i.e. up to higher temperatures than
reported so far. We discuss these results in the frame of the phenomenological
theory introduced by Dzyaloshinskii in an attempt to reach a quantitative
description of the experimental findings. We find that the anisotropy
constants, which are the drivers behind the observed behaviour, exhibit a
pronounced temperature dependence. This explains the differences in the
behaviour observed at high temperatures (above T = 18 K), where the cubic
anisotropy is weak, and at low temperatures (below T = 18 K), where a strong
cubic anisotropy induces an abrupt appearance of the tilted spirals out of the
conical state and enhances the stability of skyrmions.
