Abstract
Controlled Environment Agriculture, specifically high-density vertical farming, offers unprecedented spatial yields but often suffers from a “yield-quality trade-off,” in which accelerated biomass accumulation dilutes secondary metabolites. The primary objective of this study was to evaluate whether optimizing the vertical farm (VF) environment can uncouple rapid growth from quality degradation in sweet basil (Ocimum basilicum L.). To achieve this, we compared the agronomic, ecophysiological, and nutritional performance of eight commercial cultivars. The experiment was conducted in Switzerland characterized by a continental climate with Mediterranean influences, to compare successive harvests across two setups: an indoor, high-density hydroponic VF system (fully controlled microclimate) and a conventional soil-based greenhouse. VF cultivation accelerated the crop cycle by bypassing prolonged nursery phases, doubling temporal productivity (+106%) without compromising structural dry matter. Ecophysiologically, hydroponic plants adopted a conservative water-use strategy, halving stomatal conductance and apparent transpiration while maintaining photochemical efficiency. This adaptation triggered significant ionomic shifts: rapid carbon assimilation caused a systemic dilution of nitrogen and potassium, while unhindered root bioavailability led to luxury phosphorus uptake and increased foliar calcium despite reduced transpirational pull. Crucially, the VF system successfully broke the traditional yield-quality paradigm, producing basil with enhanced visual greenness and elevated essential oil content. However, these benefits were dictated by Genotype × Environment interactions. Elite cultivars (Adi and Prospera) exhibited high phenotypic plasticity, maximizing biomass and volatile organic compounds, whereas traditional open-field varieties struggled. Ultimately, unlocking vertical farming’s full potential relies on pairing advanced hydroponic engineering with targeted genetic selection.
1 Introduction
Controlled Environment Agriculture (CEA), and specifically high-density vertical farms (VFs), has emerged as a promising solution to address the challenges of modern food production, including urbanization, climate change, and the depletion of arable land (; ). By decoupling crop production from external environmental constraints, hydroponic vertical farms allow for year-round cultivation, optimized resource use efficiency, and maximized spatial yield (). Among high-value crops, sweet basil (Ocimum basilicum L.) is a primary candidate for indoor farming due to its rapid growth cycle, high market demand, and the premium placed on its visual and aromatic quality (; ). However, the capital-intensive nature of VF driven by artificial LED lighting and climate control, dictates the absolute necessity of maximizing biomass production and accelerating crop cycles to ensure economic viability ().
This necessity to push for maximum vegetative growth introduces a well-documented agronomic dilemma: the “yield-quality trade-off” (). In many horticultural crops, accelerated biomass accumulation under optimized, non-limiting indoor environments often results in a dilution of secondary metabolites (). For culinary herbs like basil, where commercial value is intrinsically linked to essential oil (EO) content and visual appearance (e.g., greenness and chlorophyll content), prioritizing rapid growth can inadvertently lead to an inferior final product (). Breaking this paradigm remains a critical challenge for the CEA industry.
Furthermore, the transition from conventional soil cultivation to high-density hydroponic systems drastically alters the biophysical environment of the plant. At the root level, hydroponics provides continuous, unhindered access to water and dissolved nutrients, contrasting with the complex matrix and binding constraints of soil (). At the canopy level, high planting densities alter the local microclimate, directly influencing vapor pressure deficit (VPD) and light interception (). These shifts require profound ecophysiological adjustments, particularly concerning stomatal conductance, transpiration rates, and photosynthetic efficiency (). Understanding how these physiological adaptations impact mineral partitioning, such as the well-known “dilution effect” of macronutrients like nitrogen (N) and potassium (K) during rapid growth (; ), versus the enhanced bioavailability of others like phosphorus (P) and calcium (Ca), is essential to optimize nutritional quality in soil-less systems.
Finally, while the environmental conditions in VF are meticulously controlled, the genetic component is often overlooked. The vast majority of commercial basil cultivars were traditionally bred for open-field agriculture or conventional soil-based greenhouses (). Consequently, their phenotypic plasticity and ecophysiological responses to the specific constraints and “comfort” of high-density hydroponics are largely unknown. Assessing the Genotype × Environment (G×E) interaction is therefore crucial to identify whether certain cultivars can sustain high metabolic turnover without sacrificing their aromatic and structural integrity ().
Therefore, this study aims to comprehensively evaluate the agronomic, ecophysiological, and qualitative performance of sweet basil cultivated in a high-density hydroponic VF system compared to a conventional soil-based greenhouse system. Following an initial screening of twelve basil cultivars (), we selected eight diverse genotypes based on a combination of quantitative (i.e., high biomass yield potential and growth vigor) or/and qualitative criteria (i.e., visual appeal and nutrient/aromatic profile). By evaluating these across successive harvests, we investigated: (i) the acceleration of the crop cycle and spatial productivity; (ii) leaf-level gas exchange and photochemical efficiency; (iii) systemic shifts in mineral accumulation; and (iv) the final impact on essential oil content and visual quality. We hypothesize that by selecting appropriate cultivars, an optimized hydroponic environment can successfully decouple biomass production from secondary metabolite dilution, effectively breaking the yield-quality trade-off.
2 Materials and methods
2.1 Plant material
Eight cultivars of basil plants (Ocimum sp.) were evaluated in this study (Elenora, Emma, Grand Vert, Prospera, Loki, Paoletto, Adi and Basilio). For hydroponic cultivation, two seeds were propagated in substrate plugs (Growfoam®, The Netherlands) and maintained in the nursery for 2 weeks. In conventional soil cultivation system, seeds were first sown in horticultural substrate (Type 3, Brill Substrate, Germany). Seedlings were maintained in the nursery for 4 weeks until they reached the first-leaf stage.
2.2 Hydroponic cultivation
2.2.1 Experimental set-up
The hydroponic experiment was conducted in two 10 m² controlled-climate chambers (Fitoclima 25000HP, Aralab, Portugal). Each chamber contained two vertical farming units, each consisting of three layers (2.40 x 0.80 m), resulting in a total cultivable area of 23.04 m². The cultivation system utilized ebb-and-flow tables (Stål & Plast A/S, Denmark) with perforated floating rafts. LED tubes (Kroptek, UK; 130 W m-2) were distributed to ensure homogenous light intensity (200 µmol m-2 s-1) with a 2:1 Red: Blue light ratio. Foam plugs containing seedlings were inserted into the perforated rafts to achieve a planting density of 96 plugs m-2. The experiment utilized a randomized block design, with blocks distributed across the two climate chambers and four vertical units. Treatments were replicated four times, with plot sizes ranging from 0.48 m² (half-tray) to 0.96 m² (full-tray).
2.2.2 Growth conditions
Environmental parameters were adjusted according to the specific growth stage. The photoperiod ranged between 10 and 18 hours. Temperatures were maintained at 25°C during the light period and 18°C during the dark period. Relative humidity (RH) was maintained at 70% (light) and 60% (dark). CO₂ concentrations were maintained at 800 ppm (light) and 400 ppm (dark). All environmental transitions (temperature, RH, and CO₂) occurred over a one-hour ramp.
Nutrient solution pH and electrical conductivity (EC) were automated using a Nido One device (Nido S.R.L, Italy) connected to each vertical unit. The pH was balanced using phosphoric acid (H3PO4) and potassium hydroxide (KOH). Nutrient formulations were calculated using the open-source software HydroBuddy (v1.100, Daniel Fernandez), following standard principles of hydroponic nutrient management for leafy greens (). EC was adjusted according to the growth stage. The element concentration were in ppm: 150 N, 50 P, 200 K, 80 Mg, 150 Ca, 60 S, 2.8 Fe, 0.3 Zn, 0.7 B, 0.8 Mn, 0.2 Cu and 0.05 Mo.
2.3 Soil cultivation
2.3.1 Experimental set-up
Experiments were conducted at the Agroscope research station in Conthey, Switzerland. This region, located in the Rhône Valley, is characterized by a continental climate with Mediterranean influences. The trials were carried out in a Dutch Venlo-type greenhouse. The soil texture was classified as loamy sand. Two trials were conducted during Spring 2023 and Spring 2024. The total experimental area was 200 m², divided into 60 plots (1.5 m² per plot). Each cultivar was replicated 4 times in a randomized design.
2.3.2 Growth conditions
Seedlings were transplanted into soil upon reaching the first true-leaf stage. The greenhouse climate was managed using a Senmatic system (Senmatic, Denmark). Lighting relied on natural daylight (average 15 h day-1 between April and June). Temperatures ranged from 16°C (night) to 28°C (day). Relative humidity ranged from 40% to 70%, and CO₂ was ambient (~400 ppm).
2.4 Leaf gas exchange and chlorophyll fluorescence
Stomatal conductance (gsw) and transpiration (E apparent) were assessed simultaneously using a LI-600 porometer/fluorometer (LI-COR Inc., USA). Tissue was enclosed in a 0.75 cm2 aperture clamp, held in its natural orientation to incident sunlight, with incident photosynthetic photon flux density (PPFD in μmol m−2 s−1) serving as the actinic light source, with flux density measured with a Si-photodiode quantum sensor integrated into the Li-600. Alongside the gas exchange metrics, the device recorded the operating quantum yield of photosystem II (ΦPSII) by applying a saturating multiphase light flash to light-adapted leaves. The electron transport rate (ETR) was automatically calculated by the instrument’s embedded software based on the measured 𝛷PSII, the incident photosynthetically active radiation (PAR), and standard leaf absorptance assumptions (). Measurements were taken on fully expanded young leaves under ambient light conditions, in the morning. To minimize data variability caused by diurnal fluctuations in stomatal behavior and environmental microclimate, all readings were consistently performed in the morning between 10:00 and 11:00 AM. Ten measurements were taken per replicate, twice a week throughout the cultivation period.
2.5 Relative chlorophyll content
Relative chlorophyll content was measured twice weekly using a SPAD-502Plus meter (Konica Minolta, Japan), which provides a reliable proxy for leaf greenness and absolute chlorophyll concentration (). The average of eight readings from randomly selected plants was recorded for each replicate.
2.6 Biomass and dry matter
At harvest, plants were cut at the base, and leaves were separated from stems (). Fresh weight (FW) was recorded immediately. Dry weight (DW) was determined by drying a subsample of leaves at 70°C for 72 hours. The remaining fresh leaf tissue was frozen in liquid nitrogen and stored at -80°C for subsequent analysis.
2.7 Essential oil extraction
Frozen fresh leaf samples were weighed and subjected to hydrodistillation for 2 h using a Clevenger-type apparatus (), according to the guidelines of the European Pharmacopoeia (). Essential oil content was expressed as a concentration ratio relative to fresh weight (mg/g or ‰).
2.8 Mineral content analysis
Dried leaf samples (15 g) were analyzed for macro- and micronutrients. Nitrogen (N) was determined via the Dumas method (). Carbon (C) was determined by dry combustion. Other minerals (P, K, Mg, Ca, Cu, Mn, Fe, Zn) were analyzed via Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) following hydrofluoric acid (HF) mineralization. All mineral and elemental analyses were conducted by Société Alsacienne pour le Développement et l’Etude de la Fertilité (SADEF, Aspach le Bas, France).
2.9 Statistical analysis
Data were analyzed using MATLAB (MathWorks, USA). A two-way analysis of variance (ANOVA) was employed as the primary statistical model to evaluate the main effects of the cultivation system (hydroponic vertical farm vs. conventional soil) and the genotype (eight basil cultivars), as well as their Genotype × Environment interaction. The dependent variables analyzed within this model included agronomic performance traits (e.g., fresh weight, biomass allocation), leaf-level physiological parameters (gsw, E, ΦPSII, ETR), and qualitative metrics (SPAD index, essential oil content, and mineral concentrations). Prior to the ANOVA, assumptions of normality and homogeneity of variance for all continuous variables were verified using the Shapiro-Wilk and Bartlett’s tests, respectively (p > 0.05). Where significant main effects or interactions were detected (p < 0.05), post-hoc means separations across cultivars were performed using Tukey’s Honest Significant Difference (HSD) test. Additionally, pairwise comparisons between the two cultivation systems for each individual cultivar were conducted using an unpaired Student’s t-test.
3 Results
3.1 Agronomic performance: yield, temporal productivity, and plant architecture
When evaluating global agronomic performance (Figure 1), the high-density hydroponic vertical farming system significantly outperformed the conventional soil system. The spatial yield increased by 66%, reaching an average of 1.53 kg m-2 compared to 0.92 kg m-2 in soil (p < 0.001; Figure 1A). However, the most striking advantage of the controlled environment emerged when cultivation time was factored in. The temporal productivity in the hydroponic system more than doubled, achieving 90.3 g of FW m-2 day-1 versus 43.7 g of FW m-2 day-1 in the soil system (p < 0.001; Figure 1B), underscoring a highly accelerated crop cycle.
Figure 1
Despite this explosive vegetative growth, the dry matter content (DW) remained stable, averaging 8.60% in hydroponics and 8.78% in soil, with no significant statistical difference (p = 0.22; Figure 1D). This crucial finding indicates that the hydroponic yield increase was driven by genuine structural biomass accumulation rather than mere water retention. Nevertheless, the accelerated growth and high-density set-up significantly altered plant architecture. Hydroponic plants exhibited a lower leaf-to-stem ratio (60%) than their soil-grown counterparts (68%) (p < 0.001; Figure 1C), reflecting greater resource allocation toward stem elongation since canopy density altered light microclimate and triggered rapid vertical development to support canopy competition.
The agronomic response to the hydroponic environment, however, was highly cultivar-dependent, revealing a strong G × E interaction (Supplementary Figure 1). While all eight tested varieties exhibited increased daily productivity in hydroponics, the magnitude of this response varied widely (Supplementary Figure 1D). Cultivars such as ‘Adi’ and ‘Prospera’ demonstrated phenotypic plasticity, with temporal productivity surging by 158% and 148%, respectively. In contrast, varieties like ‘Paoletto’ and ‘Grand Vert’ displayed a more conservative, yet positive, response (+69% and +73%). Importantly, the stability of the dry matter content was consistent across cultivars, with the vast majority of varieties showing no significant DW dilution in the hydroponic system (Supplementary Figure 1B), confirming the structural integrity of the accelerated crop across different genetic backgrounds.
3.2 Leaf-level physiology: gas exchange and photochemical efficiency
To understand the physiological drivers behind the accelerated biomass accumulation in the hydroponic system, leaf-level gas exchange and chlorophyll fluorescence were assessed (Figure 2). Surprisingly, despite a growth rate twice that of soil-grown plants, hydroponic basil demonstrated a highly conservative water-use strategy. Stomatal conductance (gsw) was drastically reduced by more than 50%, dropping from 0.38 mol m-2 s-1 in soil to 0.18 mol m-2 s-1 in the vertical farming set-up (p < 0.001; Figure 2A). Consequently, apparent transpiration (E apparent) followed the same systemic trend, decreasing from 4.71 to 2.16 mmol m-2 s-1 (p < 0.001; Figure 2B). This physiological adjustment strongly suggests that the high-density canopy and controlled climate of the VF created a favorable microclimate with a lower vapor pressure deficit (VPD), alleviating the plant’s need for massive transpirational cooling while maintaining optimal turgor.
Figure 2
Crucially, this substantial stomatal closure did not induce any photochemical stress or limit the photosynthetic machinery’s integrity. The quantum yield of photosystem II (Φ) remained perfectly stable across both cultivation systems, averaging 0.68 in both soil and hydroponics (p = 0.53; Figure 2C). While the electron transport rate (ETR) was lower in the hydroponic system (60.5 vs 96.9 µmol e⁻ m-2 s-1; Figure 2D), likely reflecting the specific light intensity conditions and lower transpirational demand of the indoor environment, the unaffected confirms that the hydroponic plants operated under maximal photochemical efficiency without suffering from photoinhibition.
When analyzing these traits at the cultivar level (Supplementary Figure 2), reductions in stomatal conductance and transpiration emerged as a universal, systemic response to the hydroponic environment rather than as genotype-specific traits. All evaluated cultivars exhibited a significant decrease in and when transferred to the vertical farming system (Supplementary Figures 2A, B). However, the maintenance of ΦPS2 showed slight G × E interactions. While cultivars like ‘Elenora’ and ‘Adi’ enhanced their photochemical efficiency under hydroponic conditions (p < 0.05, Supplementary Figure 2C), supporting their superior agronomic performance, others maintained their adjustments, underscoring the importance of genetic selection for optimizing indoor farming productivity.
3.3 Nutritional profile, mineral partitioning, and the yield-quality trade-off
Moving from vegetative growth to tissue composition, the mineral profile of the basil plants revealed a complex dynamic heavily influenced by the accelerated growth rate (Figure 3). Both total N and K concentrations exhibited a slight but significant decrease in the hydroponic system compared to the soil control (Figures 3A, C). Rather than indicating a systemic nutrient deficiency, this reduction illustrates a classic “dilution effect”: the explosive accumulation of carbon and fresh biomass in the VF outpaced the root system’s relative nutrient uptake rate.
Figure 3
Conversely, P concentration surged significantly in the hydroponic system (Figure 3B), highlighting the unrestricted bioavailability of orthophosphates in the circulating nutrient solution, bypassing the physical and chemical binding constraints typically found in soil matrices. Most intriguingly, Ca accumulation was also significantly higher in hydroponic plants (Figure 3D). This represents a physiological paradox: despite the drastic reduction in stomatal conductance and apparent transpiration (Figures 2A, B), which are the primary physiological drivers of passive, xylem-mediated Ca transport, the hydroponic roots efficiently absorbed and translocated Ca. This was likely facilitated by continuous, unhindered root-to-solution contact and the nutrient film’s optimal osmotic potential.
The G × E interaction heavily modulated this mineral partitioning (Supplementary Figure 3). By visualizing the relative elemental changes (Log2 fold change) across the complete macro- and micronutrient profile, the hetmap revels that while the P boost was a consistent trend across the board, the ability to resist N and K dilution was highly cultivar-dependent (Supplementary Figure 3). Furthermore, the high-density hydroponic system triggered distinct, genotype-specific accumulation and dilution patterns for various trace elements. Certain cultivars maintained stable element concentrations despite rapid hydroponic growth, making them highly suitable for maximizing nutritional stability in high-speed indoor cultivation.
Finally, a central tenet of agricultural science posits a strict trade-off between high biomass yield and the accumulation of secondary metabolites. Our findings explicitly break this paradigm for indoor-grown basil (Figure 4). Visual quality, assessed via the SPAD index, was significantly enhanced in the hydroponic set-up (p < 0.001; Figure 4B), resulting in deeper green, highly marketable leaves. This superior visual trait was conserved across almost all tested cultivars (Supplementary Figure 4B).
Figure 4
Equally critical for culinary herbs, the essential oil content, the primary determinant of aromatic quality and commercial value, was significantly elevated in the VF system (p < 0.05; Figure 4A). When dissecting this response at the cultivar level (Supplementary Figure 4A), varieties such as ‘Prospera’ demonstrated an extraordinary capacity to not only produce massive amounts of biomass but also to concentrate more volatile compounds. This simultaneous increase in spatial yield, visual appeal, and aromatic profile definitively validates the high-density hydroponic system as a superior cultivation method, provided the correct genotype is selected.
4 Discussion
4.1 The temporal advantage, light exposure and biomass allocation in vertical farming
The primary agronomic outcome of this study is the severe compression of the crop cycle in the hydroponic VF system, which bypassed the extended nursery establishment phase required in soil. This rapid establishment is primarily attributed to the unhindered root development in the aqueous solution, devoid of the mechanical impedance and fluctuating matric potential characteristic of soil (; ). Equally critical is the contrast in light exposure between the two systems. While greenhouse plants relied on dynamic and often fluctuating natural spring daylight, the VF system delivered a constant photosynthetic photon flux density (PPFD). This strict environmental control ensured a stable daily light integral (DLI), preventing weather-induced photosynthetic bottlenecks and directly fueling the high temporal productivity (a 106% increase in daily biomass generation. However, this accelerated growth triggered a shift in plant architecture. The reduction in the leaf-to-stem ratio suggests a shade-avoidance response or enhanced stem elongation driven by the high planting density (96 plants/m²). In a competitive canopy, the plant reallocates carbon toward stem structural biomass to maximize light interception, a recognized morphogenic adaptation in dense CEA environments (; ). Furthermore, the specific LED spectral quality (2:1 Red: Blue) combined with mutual shading in the dense canopy likely amplified this photomorphogenic elongation compared to the full-spectrum natural sunlight of the greenhouse.
4.2 Ecophysiological “comfort” and the calcium paradox
The drastic reduction in stomatal conductance and apparent transpiration in hydroponic plants, coupled with a stable ΦPS2, indicates that the VF environment placed the basil plants in a state of physiological “comfort”. The controlled indoor climate likely maintained an optimal VPD, reducing the atmospheric demand for transpirational cooling (). Consequently, plants could afford a conservative water-use strategy without triggering thermal stress or photoinhibition, as the photosynthetic machinery remained uncompromised. This reduced transpirational flow introduces a physiological paradox regarding Ca accumulation. Calcium is a xylem-mobile nutrient, and its uptake and translocation to shoot tissues are canonically driven by transpirational pull (; ). One would expect the 50% drop in transpiration (Figure 2B) to induce Ca deficiencies (e.g., tipburn). Surprisingly, our nutrient profiling revealed a significant increase in foliar Ca in the hydroponic plants suggesting that in high-density VF, continuous root exposure to a bioavailable nutrient solution, combined with active root pressure during the dark period, more than compensates for the reduced daytime transpirational pull, ensuring structural integrity of the cell walls.
4.3 Nutrient dilution vs. bioavailability
The mineral profile of the hydroponic basil perfectly illustrates the “dilution effect” originally described by and frequently observed in fast-growing hydroponic crops (). The reductions in total foliar N and K do not reflect an impoverished nutrient solution, but rather the mathematical consequence of rapid carbon assimilation. The plant generates structural biomass (sugars, cellulose) faster than the roots can uptake and partition these specific mobile ions. Conversely, the increase in foliar P highlights the inherent advantage of hydroponics: the elimination of soil binding constraints. In conventional soil, orthophosphates rapidly precipitate with Ca or iron, becoming largely unavailable to roots (; ). In our VF system, P remained fully soluble and continuously bioavailable, leading to luxury consumption that likely supported the high metabolic turnover and rapid ATP generation required for such fast growth.
4.4 Breaking the yield-quality trade-off through genotype selection
The central hypothesis of this study was that the traditional “yield-quality trade-off” could be broken in CEA. Our results on essential oil content and SPAD index support this. Not only did the hydroponic plants produce more biomass in less time, but they also synthesized a higher concentration of secondary metabolites and chlorophyll. This challenges the Growth-Differentiation Balance Hypothesis (), suggesting that when all primary abiotic stresses (water, nutrition, optimal light) are removed, the plant possesses sufficient carbon budget to simultaneously fuel cellular division and secondary metabolic pathways. This paradigm shift is corroborated by recent evidence across other high-value crops cultivated in precision indoor environments. For example, optimized hydroponic and lighting strategies have been shown to simultaneously boost both total harvestable biomass and the accumulation of secondary metabolites, such as anthocyanins and phenolics in lettuce (; ), as well as cannabinoids and terpenes in medicinal plants like Cannabis sativa (). These findings across diverse taxa demonstrate that the traditional yield-quality trade-off can be systematically uncoupled in stress-free, resource-abundant agricultural systems. However, the realization of this potential is dictated by genetics. The G × E interactions observed emphasize that not all cultivars are equipped for indoor farming. Cultivars like ‘Adi’ and ‘Prospera’ exhibited high phenotypic plasticity, acting as “High-Responders” that maximized the VF technological advantage. Conversely, traditional open-field varieties like ‘Basilio’ struggled to translate the environmental comfort into qualitative gains.
5 Conclusion
The primary objective of this study was to evaluate whether optimizing a high-density hydroponic vertical farming (VF) environment could uncouple rapid biomass accumulation from the dilution of secondary metabolites in sweet basil. Our findings confirm that the conventional yield-quality trade-off can be successfully broken in controlled environments. By accelerating the crop cycle, particularly during the critical nursery and establishment phases, the VF system increased temporal productivity by 220% to over 360% compared to conventional soil cultivation. Physiologically, the plants adapted to the indoor microclimate by adopting a conservative stomatal behavior while maintaining photochemical efficiency, which led to to altered nutrient partitioning, including increased calcium accumulation despite reduced transpiration. Ultimately, the hydroponic system yielded basil with higher visual greenness (SPAD) and elevated essential oil content, effectively breaking the conventional yield-quality trade-off. However, this agronomical response is strongly genotype-dependent. The advancement of indoor agriculture relies on pairing environmental engineering with the targeted selection of responsive cultivars, such as ‘Adi’ and ‘Prospera’, that possess the genetic capacity to thrive in controlled conditions.
Statements
Data availability statement
The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.
Author contributions
GC: Data curation, Investigation, Methodology, Writing – review & editing. MM: Investigation, Writing – review & editing. RF: Resources, Writing – review & editing. PB: Conceptualization, Writing – review & editing. FG: Conceptualization, Writing – review & editing. NR: Conceptualization, Funding acquisition, Writing – review & editing. SY: Conceptualization, Funding acquisition, Resources, Writing – review & editing. ChC: Conceptualization, Funding acquisition, Methodology, Supervision, Writing – review & editing. ZS: Conceptualization, Resources, Funding acquisition, Project administration, Writing – review & editing. CéC: Conceptualization, Funding acquisition, Methodology, Project administration, Supervision, Writing – review & editing. DT: Conceptualization, Data curation, Formal analysis, Methodology, Supervision, Writing – original draft, Writing – review & editing, Investigation, Resources, Validation.
Funding
The authors declared that financial support was received for this work and/or its publication. This work was funded by Innosuisse, the Swiss Innovation Agency, grant #54107.1 IP-LS, LOFT -Local food for the future.
Acknowledgments
The authors gratefully acknowledge the financial support of Innosuisse and Fenaco.
Conflict of interest
The authors declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Generative AI statement
The authors declared that generative AI was not used in the creation of this manuscript.
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Supplementary material
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fagro.2026.1866628/full#supplementary-material
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Summary
Keywords
controlled environment agriculture, essential oils, hydroponics, phenotypic plasticity, sweet basil, vertical farming, yield-quality trade-off
Citation
Carron G, Maret M, Farinet R, Bosshard P, Gartmann F, Rüegg N, Yildirim S, Carlen C, Schmautz Z, Camps C and Tran D (2026) Trade-offs between yield, physiological performance, and quality in basil (Ocimum basilicum) cultivated in hydroponic versus conventional soil-based greenhouse system. Front. Agron. 8:1866628. doi: 10.3389/fagro.2026.1866628
Received
27 April 2026
Revised
15 June 2026
Accepted
20 July 2026
Published
13 August 2026
Volume
8 - 2026
Edited by
Stefania De Pascale, University of Naples Federico II, Italy
Reviewed by
Barbara Almeida Dutra, Universidade Estadual do Sudoeste da Bahia, Brazil
Ajay Dhukuchhu, University of California, United States
Updates
Copyright
© 2026 Carron, Maret, Farinet, Bosshard, Gartmann, Rüegg, Yildirim, Carlen, Schmautz, Camps and Tran.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Daniel Tran, qnoctnandaniel.tran@agroscope.admin.ch
Disclaimer
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