Chūnhuà zuòyòng shì zhíwù kāihuā qián de bìyào jiēduàn.
Vernalization is a necessary stage before flowering in many plants.
Tips
usage
春化 is a botany / agronomy term. The full technical phrase is 春化作用 (chūnhuà zuòyòng, 'vernalization effect'). Outside of biology textbooks the word almost never appears.