Method for increasing essential oil content of michelia chapensis

The method comprises the following steps that (1) the tops of michelia chapensis seedlings are covered with a sunshade net, the light transmittance of the sunshade net ranges from 75% to 85% during March to July, the light transmittance of the sunshade net ranges from 35% to 45% during August to October, full-natural illumination is achieved during November to February of the next year, and meanwhile fertilizer is sprayed every 25 days to 35 days during April to September; (2) picking fresh leaves of michelia chapensis from the second year of planting, and extracting essential oil; according to the method disclosed by the invention, by strictly adjusting illumination conditions and fertilization modes in different months in the growth process of michelia chapensis and cooperating with the opportunities of branch and leaf pruning, fresh leaf picking and essential oil extraction, the plant fresh leaf weight and fresh leaf oil yield of michelia chapensis seedlings are greatly improved, so that the total oil yiel