Supplemental lighting can enhance yield when sunlight is limited, as in winter. As the effect
of frequent cloudy or rainy days in other seasons on plant growth and yield remains unclear,
this article investigated the effect on tomato (Solanum lycopersicum) and compensation by supplemental LED inter-lighting. The results clearly show that supplemental LED inter-lighting
could efficiently compensate for a shortage of light for plant growth, photosynthesis and thus
yield under the lack of sunshine.