###### Abstract  
This study aims to optimize artificial LEDs light conditions, for \"Genovese\" basil germination and growth in an indoor environment suitable for horticulture. Following a previous study on the synergic effect of LEDs light and a tailored fertilizer, in this study, the effect of white LED in combination with hyper red and deep blue, as well the plants-lights distance, was correlated to 14 growth and germination parameters, such as height, number of plants, etc. A design of experiments approach was implemented, aiming to derive mathematical models with predictive power, employing a restrained number of tests. Results demonstrated that for the germination phase, it is not possible to derive reliable mathematical models because almost the same results were found for all the experiments in terms of a fruitful germination. On the contrary, for the growth phase, the statistical analysis indicates that the distance among plants and lights is the most significant parameter. Nevertheless, correlations with LED light type emerged, indicating that white LEDs should be employed only to enhance specific growth parameters (e.g., to reduce water consumption). The tailored models derived in this study can be exploited to further enhance the desired property of interest in the growth of basil in horticulture. bsail; design of experiments; LED +
Footnote †: journal: Medical  
light it is possible to meet plants requirements, therefore improving the overall growth efficiency [2,3]. For example, low irradiance leads to a less controlled leaves growth, breaking the optimization mechanism that regulates the leaf area per unit necessary to maximize the light interception [4] in the growth period of the plants. In addition, an increased efficiency in plant germination and growth, by a precise control over artificial light, can be a relevant opportunity for environments where natural light is naturally absent, such as northern latitude countries or space travel. Artificial light optimization can be beneficial for leafy greens and herbal crops that are an exceptional source of various human health-promoting macronutrients such as polyphenols, vitamins, and essential oils [5]. For this reason, for these plants, the relationship between artificial light and physiology under different light spectra and/or light intensities is attracting the interest of the more recent research [6,7]. Among leafy greens, _Ocimum basilicum_ L. (Basil) belonging to the _Lamiaceae_ family is a worldwide-spread herbal crop employed as culinary herb and for essential oil extraction, as well as, widely used in medical industry as component of oral health products and to treat several medical complaints such as gastrointestinal disorders, headaches and stomach aches [8,9]. Considering the beneficial effect on human health and nutrition, basil is considered one of the best candidates to study its potential germination and growth optimization through artificial light [10]. As artificial light source for plant cultivation, light-emitting diodes (LEDs) have received considerable attention as they have the capability to produce a considerable light intensity with low radiant heat output for years, compared to fluorescent lamp, therefore with an increased lifespan [11]. Compared to incandescent light's 1000 h and fluorescent light's 8000 h life span, LEDs have a significantly longer life of 100,000 h [12]. In addition, by using well-tailored LEDs-based arrays, it is possible to have a full control of the spectral composition and an adjustment of light intensity for a specific plant or growth period. In terms of power consumption, the beneficial effect related to the use of LEDs as light source is twofold [13, 14, 15]. First, it is well known that, for a given light intensity, the power consumption of a generic LED lamp is significantly lower than any other artificial light source.