In the development of modern facility agriculture, tomatoes, as the world's second-largest vegetable crop, face significant lighting challenges in facility-based production. According to data from the International Society for Horticultural Science, insufficient lighting is the primary factor limiting greenhouse tomato yield and quality, directly affecting fruit sugar-acid ratio, lycopene content, and vitamin C accumulation.
Tomato photosynthesis primarily relies on photosynthetically active radiation (PAR) in the 400-700nm wavelength range, where 660nm red light promotes flowering and fruiting, 460nm blue light regulates plant morphology, and PPFD (Photosynthetic Photon Flux Density) levels directly determine photosynthetic efficiency.
According to the "Technical Specification for Supplemental Lighting in Protected Horticulture" (NY/T 2671-2014) and experimental data from the Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, tomato PPFD requirements at different growth stages show stepped changes: the seedling stage requires maintenance at 150-200 μmol/m²·s to prevent excessive elongation, the flowering and fruit-setting stage needs elevation to 250-300 μmol/m²·s to promote flower bud differentiation and fruit expansion, while the fruit coloring stage requires maintaining 200-250 μmol/m²·s with an appropriate increase in red light ratio (R: B=2:1) to enhance lycopene synthesis.
The specification also emphasizes that Daily Light Integral (DLI) should reach 15-20 mol/m²·d to meet the requirements for premium tomato production.
Project Overview
This project serves a modern tomato production base in East China, with an operational area of 1,460㎡ (two 730㎡ smart greenhouses), using substrate cultivation methods, producing approximately 45 tons of premium tomatoes annually.
Customer Needs Analysis
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Insufficient Light Intensity: During winter and spring, natural light PPFD is only 120-180 μmol/m²·s, far below the 250-300 μmol/m²·s standard required for tomato flowering and fruiting, leading to a 15-25% decrease in fruit-setting rate.
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Poor Light Uniformity: Traditional supplemental lighting solutions have "hot spots" and "shadow zones," causing size inconsistency in the same batch of fruits, reducing marketability by approximately 20%.
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High Energy Costs: The existing HPS (High-Pressure Sodium) lighting system has an efficacy of only 1.8 μmol/J, with electricity costs accounting for 35% of production costs.
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Frequent System Maintenance: HPS bulbs have an average lifespan of 8,000 hours, requiring frequent replacement that affects normal production and increases labor costs.
Natural Light Limitation Analysis
Based on on-site monitoring data from TheOneGrow team, greenhouse tomato production faces the following lighting challenges:
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Seasonal Light Deficiency: From November to February, the average daily PPFD integral (DLI) in East China greenhouses is only 8-12 mol/m²·d, while optimal tomato growth requires a light integral of 15-20 mol/m²·d.
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Spectral Composition Imbalance: Glass and film materials have lower transmittance for blue-violet light (400-500nm), leading to plant elongation, internode stretching, and affecting fruit quality.
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Uneven Light Distribution: Greenhouse structural obstructions cause edge area PPFD values to be 30-40% lower than central areas, resulting in significant plant growth differences.
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Decreased Photosynthetic Efficiency: When PPFD falls below 200 μmol/m²·s, tomato net photosynthetic rate significantly decreases, reducing single fruit weight by 20-30%.
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Abnormal Sugar Metabolism: Insufficient red light affects soluble sugar accumulation in fruits, reducing sugar content by 1-2°Brix and decreasing market value.
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Weakened Stress Resistance: Insufficient lighting leads to decreased plant disease resistance, with gray mold incidence increasing by 15-25%.
TheOneGrow Tomato Cultivation Supplemental Lighting Solution
Based on photosynthetic physiology principles and years of project experience, TheOneGrow has designed a technical solution of "zoned precision lighting + intelligent control":
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Fixture Configuration: Uses independently developed 320W full-spectrum LED top supplemental lights with efficacy reaching 2.9 μmol/J (DLC Premium certified), equipped with patented cooling systems.
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Spectral Design: 660nm red light accounts for 35%, promoting flowering and fruiting; 460nm blue light accounts for 20%, controlling plant form; full-spectrum design simulates natural sunlight, with Spectral Quality Index (SQI) reaching 85.
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Layout Strategy: Arranged with 4×2.5m spacing, 145 supplemental lights installed per greenhouse, suspended 80cm above the canopy, ensuring ground PPFD values reach 280±20 μmol/m²·s, with uniformity coefficient (Uo) >0.8.
Project Implementation Results
From February to June 2024, we implemented the supplemental lighting solution for this tomato base. During project execution, the TheOneGrow technical team faced and resolved multiple practical challenges:
Light Uniformity Optimization Challenge: Initial testing revealed that the north and south sides of the greenhouse had PPFD values 32% lower than the central area due to structural beam and column obstructions. We achieved breakthroughs through the following measures:
- Added compensating light positions in edge areas, increasing fixture density from the standard 20 units/100㎡ to 23 units/100㎡
- Adopted dynamic dimming technology, with edge fixture power settings at 110% and central areas at 90%
- Installed a light sensor network (1 monitoring point per 150㎡), real-time monitoring and automatic adjustment of light intensity in each zone
Pre-Implementation Status:
- Average single fruit weight: 185g
- Sugar content: 4.2°Brix
- Yield per plant: 8.5kg
- Energy consumption: 0.85 kWh/kg tomatoes
Post-Implementation Results:
- Average single fruit weight: 235g (+27%)
- Sugar content: 5.8°Brix (+1.6°Brix)
- Yield per plant: 11.2kg (+32%)
- Energy consumption: 0.52 kWh/kg tomatoes (-39%)
General Manager Li of the East China modern tomato production base stated: "TheOneGrow's supplemental lighting system doubled our winter tomato production, with sugar content consistently above 5.5°Brix. The return on investment came six months earlier than expected."
About TheOneGrow
TheOneGrow, established in 2023, is a leading domestic plant lighting equipment manufacturer, specializing in facility agriculture light environment technology research and development for 13 years. The company has a complete product R&D, production, sales, and service system, establishing long-term cooperative relationships with authoritative institutions such as the Chinese Academy of Agricultural Sciences and South China Agricultural University.
Products have been applied to commercial agricultural projects in over 10 countries and regions worldwide, including glass greenhouse clusters in the Westland region of the Netherlands, vertical farms in BC Province, Canada, and organic tomato bases in Queensland, Australia.