*Article* **Statistical Optimization of a Hyper Red, Deep Blue, and White LEDs Light Combination for Controlled Basil Horticulture**

**Silvia Barbi 1,\*, Francesco Barbieri 2, Alessandro Bertacchini 2,3 and Monia Montorsi 2,3**


**Featured Application: The specific application of this work is related to basil cultivation in indoor horticulture under artificial light. This work is devoted to the investigation of specific light combinations, based on hyper red, deep blue, warm white LEDs, to promote basil germination and growth. The aim is to improve basil's yield and quality by reducing the overall growth cycle at the same time.**

**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.

**Keywords:** basil; design of experiments; LED
