A method for adjusting the spectrum of a lighting for plants (1). The method adjusts an LED excitation source (3) and a florescent powder (4), where the type and ratio of a chip of the LED excitation source is comprised, and the type and ratio of the florescent powder is also comprised. These adjustments are determined on the basis of different needs (6) of various plants for the spectrum, thus allowing for a great increase in the degree of freedom in adjusting the spectrum. In addition, the needs of the plants for different spectra are met by changing an LED lighting optical component (5), thus allowing for greatly convenient manufacturing and ultimate application of the lighting.
