The invention provides a horticulture lighting system (100), comprising (i) a lighting device (110) configured to provide horticulture light (111) and (ii) a control system (200) configured to control the horticulture light (111), wherein the control system (200) is further configured to provide according to a predetermined time scheme and/or as function of a sensor signal a pulse of horticulture light (111) in a spectral wavelength region at least comprising blue light (112) during a pulse period selected from the range of 1-60 min.