The aim of controlled-environment experiment was to assess the effects of semiconductor laser light on the early growth stages of Setaria pumila and Berteroa incana, whose seeds had previously been exposed to direct artificial light at night (ALAN). Seeds were collected from two maize fields differing in nighttime light pollution: 1. a site in Siechnice (Wrocław County), located near the “Siechnice” horticultural complex emitting intense nocturnal illumination, 2. a control site in Jelcz-Laskowice (Oława County), situated c.a. 12 km from the emission source. The collected seeds were subjected to presowing laser irradiation at three energy levels: three-fold, five-fold, and seven-fold of the base dose of 0.25 J·cm⁻², with an exposure time of 4.1 min. Non-irradiated seeds served as the control. The study proved that the root length of seedlings of both species originating from the ALAN-exposed site was significantly reduced compared with plants from the light-pollution-free area. There were also differences in germination capacity of Setaria pumila seeds – those collected from ALAN-exposed site germinated significantly weaker than obtained from ALAN-free location. Laser irradiation stimulated seedling growth; however, this response was more pronounced in plants originating from the environment without nocturnal artificial lighting.