RAISING SEEDLING ILLUMINATING METHOD AND DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a raising seedling illuminating method and device therefor which obtains sufficient raising effect and is excellent economically. SOLUTION: Supplemental lightening is executed so as to irradiated the light of desirably at least PPFD 60μmol.m<-2> .s<-1> light quantity to a growing seedling. For example, metal halide, sodium lamp or an ultra high pressure sodium lamp is arranged within a glass greenhouse to automatically turn on almost two hours before sunrise and to turn off at the time of sunrise.