Plants being immobile in nature exhibits a remarkable plasticity in adapting to variations in light conditions such as spectral quality, photon flux, and photoperiod [1,2]. The regulation of plant growth and development in response to light, known as photomorphogenesis, is governed by various photoreceptors [3,4]. Among the light spectra, red (600–700 nm) and blue (400–500 nm) light wavelengths are particularly important for plant growth, as chlorophyll a and b efficiently absorb these wavebands, enhancing the quantum of photosynthesis compared to other spectral ranges [5,6]. Red light (RL) has been shown to improve stomatal functionality, increase dry matter production, and enhance leaf area [7], while blue light (BL) is known to regulate stomatal behavior, chloroplast development, and phototropism [[8], [9], [10]]. The use of light-emitting diodes (LEDs) have received a fair share of scientific and industrial interest, particularly in horticulture crop due to their energy efficiency and ability to precisely management of required light spectra [[11], [12], [13], [14], [15], [16], [17], [18], [19]]. Some studies suggested that red light suppresses plant height and flowering while promoting lateral shoot elongation, whereas blue light enhances shoot elongation and flowering in certain crops, such as petunia [20]. Combining red and blue light has been found to enhance pigment content, and physiological responses in lilium [[21], [22], [23]]. The use of LEDs, particularly in the blue, red, and combined blue-red spectra, has been shown to induce desirable photomorphogenic responses, enhancing plant growth, and manipulating flowering time in ornamental crops [24,25].

Lilium, a facultative long-day plant, can grow under various light conditions but requires long days for optimal flowering [26]. Due to its increasing demand in the cut-flower market, where lilium ranks fourth in the Netherlands, commercial production has been on the rise [27]. The global cut-flower market, estimated as USD 39.08 billion in 2024, is expected to reach USD 51.83 billion by 2030, growing at a compound annual growth rate (CAGR) of 4.8 % [27]. Commercial lilium cultivation is typically performed in greenhouse conditions, where temperatures range between 10 and 17 °C at night and 16–21 °C during the day [[28], [29], [30]]. The impact of specific light spectral treatments on lilium's morphological and physiological traits, especially under high-density soil-less systems, remains under explored. Previous studies have emphasized the importance of optimizing light conditions to improve lilium traits such as plant height, stem diameter, bud development, and vase life [26]. However, limited attention has been given to the role of light in regulating pigment accumulation, antioxidant activity, and the expression of flowering-related genes in lilium [31]. Moreover, conventional agricultural methods for lilium production face challenges such as yield variability, rising labor costs, disease outbreaks, limited agriculture land, and climate change issue [32]. Therefore, the climate-controlled soil-less systems allow precise management of nutrients and environmental parameters, leading to consistent, high-quality flower production year-round, manipulate flowering time and post-harvest longevity, irrespective of seasonal variations [[32], [33], [34], [35]].

Commercial floriculture can be revolutionized by the integration of LED illumination and automated greenhouse technology, which increases productivity, lowers expenses, and permits year-round cultivation. By providing exact light spectra (BL + RL, for example), LEDs improve photosynthesis, leading to more biomass production, richer colors, and better flower quality. LEDs are more sustainable than traditional lighting since they consume 40–70 % less energy, produce less heat, and cost less to operate. Artificial intelligence (AI)-powered climate control, intelligent irrigation, and remote monitoring further reduce labor costs by guaranteeing effective management with less manual labor.

Therefore, the present study is designed to investigated the influence of different light spectrum supplementation (blue, red, blue + red, and white as control) on the morphological traits, chlorophyll content index (CCI), and biochemical composition along with key associated genes that regulated the flowering in lilium plants grown in a soil-less pin tray system within an autonomous climate-controlled greenhouse. We hypothesize that blue and red-light treatments will have a synergistic effect on promoting plant height, bud development, and vase life while enhancing chlorophyll and carotenoids content throughout development. Additionally, we examine the expression of key flowering-related genes to uncover the molecular regulation underlying photomorphogenic responses in lilium under varying light treatments.