Light-emitting diodes (LEDS) are a potential lighting source for space-based plant growth systems because of their small mass, operational longevity, and spectral quality. However, the vegetative and reproductive growth and development of plants grown under narrow spectrum LEDs must be characterized before acceptance of LEDS as an alternative light source for growing plants. The objectives of this study were 1) to determine the feasibility of using red LEDS for growing Arabidopsis thaliana L. through a full seed-bearing generation, and 2) to determine if supplemental blue radiation is necessary for growth and seed production. Arabidopsis grown under red LEDS alone produced viable seed, but these plants had abnormal leaf morphology and delayed flowering in comparison to control plants grown under broad spectrum white light or red LEDS supplemented with blue light.