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In times of major environmental challenges and increasing demand for forest products, planted forests have acknowledgedadvantages compared to other land uses. Despite not being able to completely take the place of natural forests, planted ones have,if properly managed, great potential to contribute in addressing these problems. Besides the ecological benefi ts such as carbonsequestration, planted forests can help meet the demand for wood products without further depletion of the natural forest. Forestrestoration, rehabilitation, and reforestation are limited by the capacity for producing forest regeneration materials. Often, asproduction is intensifi ed at forest nurseries, the practices begin to have an adverse impact on the environment and stop being trulysustainable. One of the main issues in nurseries is the energy consumption for grow lights during periods of short daylight.By using high-effi ciency LED grow lamps and adjusting the light intensity, this study aimed to reduce the energy consumptionfrom lighting per seedling without compromising seedling development. The precultivation of Picea abies and Pinus sylvestrisseedlings was done during 5 weeks under controlled conditions at 20 °C and a relative humidity of 60%. The photoperiod was16 hours at an intensity ranging from 50 to 350 μmol/m2/s in intervals of 50 μmol/m2/s intervals.