The main purpose of this work was to con rm the previously proposed model of the laser radiation interaction with the epidermal layer of monocotyledons cells. The other purpose was to show that plant age affects polarization parameters and polarization direction affects plant development.The methods used in this work include the development of LED light sources, the polarization parameters assessment (polarization index) and statistical analysis. The maize plants (Zea mays L.), variety "Early gourmet 121", optical setup and software TXP Series Instrumentation were used in the work. Plants were grown under white light (WW) at an intensity of 200 µmol m − 2 s − 1 .The study established that the harmonic ellipticity polarization change by ± 12.0° occurs when the linearly polarized light passed through the maize leaves depending on the axis rotation angle of the epidermal cells. In addition, it was shown that the maize leaves of different ages could have different values of the refractive index anisotropy, and, consequently, different polarization ellipticity index.It has been established that the maize leaves with ordered structure of epidermal cells are able to change the polarized radiation ellipticity. That con rms the previously proposed model of the polarized light interaction with plant leaves. We established that linearly polarized light passing through the leaves of maize plants turns into elliptically polarized light, which is able to interact more effectively with the photosensitive protein structures of the leaf inner cells.