A tale of precision, patience, and the pursuit of hydroponic perfection
In the controlled environment of modern agriculture, few crops capture the imagination quite like bok choy—that elegant Asian brassica that transforms from tiny seed to harvestable perfection in just 45 days when blessed with the right conditions. Sarah Chen discovered this truth during her first season managing the university’s hydroponic research facility, where every nutrient molecule counted and every environmental parameter held the key to either triumph or failure.
The morning sun filtered through the greenhouse panels as Sarah checked her nutrient reservoirs, the familiar hum of water pumps creating a symphony of controlled agriculture. Today marked the beginning of another bok choy cycle, and she knew that success would depend entirely on her understanding of this remarkable crop’s precise nutritional demands and her ability to translate that knowledge into actionable growing protocols.
Chapter One: Understanding the Varieties and Their Unique Demands
Sarah’s mentor, Dr. Martinez, had taught her that bok choy varieties weren’t simply different colors and sizes—each cultivar presented distinct nutritional requirements that could make or break a hydroponic operation.
Shanghai Bok Choy stood as the workhorse variety, with its thick white stems and dark green leaves requiring robust nutrition throughout its compact 35-45 day cycle. In Sarah’s hydroponic systems, Shanghai varieties demanded elevated potassium levels (280-320 ppm) to develop those characteristic thick, succulent stems that commanded premium prices in Asian markets.
“The stems tell the story,” Dr. Martinez had explained during Sarah’s first week. “Inadequate potassium produces thin, fibrous stems that no chef wants. But get the nutrition right—280 to 320 parts per million potassium in your solution—and those stems become crisp, sweet perfection.”
Baby Bok Choy varieties like ‘Toy Choy’ and ‘Mini Me’ presented different challenges entirely. These diminutive plants required intensive nutrition in compressed timeframes, with nitrogen demands reaching 200-240 ppm during their rapid 25-30 day growth cycles. Sarah learned to treat them like nutritional athletes, feeding them concentrated solutions that would overwhelm larger varieties.
Purple Top varieties added visual appeal but came with specialized requirements. The anthocyanin production responsible for their stunning purple coloration demanded elevated levels of phosphorus (50-70 ppm) and specific micronutrient combinations that Sarah had spent months perfecting through careful experimentation.
Heat-tolerant varieties like ‘Summerfest’ and ‘Heat Wave’ required adjusted nutrition programs during warm months, with increased calcium levels (200-240 ppm) and specialized stress-response nutrients to maintain quality when temperatures climbed above the optimal range.
Chapter Two: System Selection and the Foundation of Success
The choice of hydroponic system represented Sarah’s first critical decision each season. She had experimented with every major system type, learning through both success and expensive failure that bok choy’s specific growth habits demanded particular approaches.
Deep Water Culture Systems had become Sarah’s preferred method for bok choy production, providing the aggressive root aeration these brassicas demanded. She maintained solution depths of 8-10 inches with continuous aeration delivering 1.0-1.5 CFM per gallon of nutrient solution. The dissolved oxygen levels never dropped below 6 ppm—a lesson learned after losing an entire crop to root rot during her second month.
“Oxygen is life in hydroponics,” she reminded her students during facility tours. “Bok choy roots are particularly sensitive. Drop below 5 ppm dissolved oxygen, and you’ll see brown, slimy roots within 48 hours. Maintain 6-8 ppm, and those roots stay white, healthy, and actively uptaking nutrients.”
Nutrient Film Technique channels worked exceptionally well for baby bok choy varieties, with their shallow root systems adapting perfectly to the thin nutrient film. Sarah used 4-inch wide channels with 1:40 slope ratios, maintaining flow rates of 1.5-2.0 liters per minute per channel. The key was maintaining that perfect 2-3mm film depth—too shallow and roots dried out, too deep and oxygen levels dropped.
Ebb and Flow systems provided excellent versatility for mixed variety production. Sarah’s flood cycles ran every 3-4 hours during daylight periods, with complete drainage between cycles ensuring optimal root aeration. The 2-inch flood depth provided adequate nutrient contact while preventing the waterlogged conditions that plagued less experienced growers.
Media-based drip systems offered the most forgiving approach for beginners, using expanded clay pebbles or rockwool cubes with precise drip irrigation. Sarah’s systems delivered 15-20% drainage volume through pressure-compensated emitters, ensuring uniform nutrient distribution across all growing positions.
Chapter Three: The Art and Science of Nutrient Formulation
Creating the perfect nutrient solution for bok choy had become Sarah’s obsession. Every morning began with testing pH and electrical conductivity, adjusting concentrations with the precision of a chemist and the intuition of a master grower.
The Foundation Formula represented months of refinement:
Primary Macronutrients (Peak Growth Formulation):
- Nitrogen (N): 180-220 ppm (balanced 60% nitrate, 40% ammonium)
- Phosphorus (P): 45-60 ppm
- Potassium (K): 280-320 ppm
- Calcium (Ca): 180-220 ppm
- Magnesium (Mg): 60-80 ppm
- Sulfur (S): 80-100 ppm
Essential Micronutrient Complex:
- Iron (Fe): 3.0-4.5 ppm (chelated Fe-DTPA for pH stability)
- Manganese (Mn): 1.0-1.5 ppm
- Zinc (Zn): 0.4-0.6 ppm
- Copper (Cu): 0.15-0.25 ppm
- Boron (B): 0.4-0.6 ppm
- Molybdenum (Mo): 0.06-0.10 ppm
Critical Solution Parameters:
- pH: 5.8-6.4 (optimal range 6.0-6.2)
- Electrical Conductivity: 1.8-2.6 dS/m
- Total Dissolved Solids: 1,260-1,820 ppm
- Solution Temperature: 64-70°F (18-21°C)
- Dissolved Oxygen: 6-8 ppm minimum
Sarah had learned that these numbers weren’t suggestions—they were the difference between mediocre bok choy and the premium specimens that commanded top prices at local restaurants. Every deviation told a story written in leaf color, stem thickness, and final harvest weight.
Chapter Four: The Growth Cycle Chronicles
Each growth stage brought its own nutritional drama, and Sarah had developed feeding programs that responded to bok choy’s changing needs with surgical precision.
The Germination Period (Days 1-7):
Sarah’s propagation area maintained constant vigilance during this critical phase. Seeds nestled in rockwool cubes received gentle nutrition through diluted solutions that would seem inadequate to the uninitiated but provided exactly what germinating seeds required.
- EC: 0.6-1.0 dS/m
- N: 60-100 ppm
- P: 25-35 ppm
- K: 80-120 ppm
- Ca: 60-100 ppm
- pH: 5.8-6.1
“Think of seedlings as newborns,” Sarah explained to visiting students. “Too much nutrition burns them. Too little starves them. This narrow window of 0.6 to 1.0 electrical conductivity gives them exactly what they need to establish those crucial first roots.”
Temperature control proved critical during germination. Sarah maintained propagation temperatures at 72-76°F, using heating mats beneath the seed trays. Humidity domes kept relative humidity at 85-90% until emergence, typically occurring on day 4-5 under optimal conditions.
The Establishment Phase (Days 8-18):
As cotyledons gave way to true leaves, Sarah gradually increased solution strength. This transition period demanded careful observation—too rapid an increase in nutrients would shock young plants, while insufficient nutrition would create weak foundations for later growth.
- EC: 1.2-1.6 dS/m
- N: 120-160 ppm
- P: 35-45 ppm
- K: 160-200 ppm
- Ca: 100-140 ppm
- pH: 5.9-6.3
The calcium requirement during this phase couldn’t be overstated. Sarah had learned through painful experience that calcium deficiency during establishment created weak cell walls that plagued plants throughout their entire growth cycle. She monitored new leaf development daily, watching for the subtle signs of calcium stress that appeared as slight distortions in leaf edges.
Vegetative Growth Explosion (Days 19-35):
This phase separated successful growers from amateurs. Bok choy’s rapid leaf expansion created enormous nutritional demands that required aggressive feeding programs. Sarah’s plants consumed nutrients with voracious appetite during this period.
- EC: 1.8-2.4 dS/m
- N: 180-220 ppm
- P: 45-60 ppm
- K: 280-320 ppm
- Ca: 180-220 ppm
- pH: 6.0-6.4
“Watch the consumption rate,” Sarah would tell her assistants. “During peak growth, healthy bok choy plants consume 2-3 liters of solution per square meter daily. If consumption drops, something’s wrong—check your oxygen levels, pH, or look for root problems.”
The potassium demand during this phase was particularly intense. Sarah had learned that insufficient potassium produced bok choy with thin, weak stems that had no commercial value. Maintaining 280-320 ppm potassium created those thick, succulent stems that made her crops sought after by area chefs.
Pre-Harvest Optimization (Days 36-45):
The final growth phase required strategic nutrition adjustments to optimize flavor, texture, and storage life. Sarah reduced nitrogen levels slightly while maintaining other nutrients to prevent excessive nitrate accumulation.
- EC: 2.0-2.6 dS/m
- N: 160-200 ppm (reduced from peak levels)
- P: 50-65 ppm
- K: 300-340 ppm (increased for quality)
- Ca: 200-240 ppm (elevated for storage life)
- pH: 6.1-6.4
This period determined final quality. Adequate calcium during pre-harvest phase meant bok choy that maintained crisp texture for 10-14 days post-harvest, while calcium-deficient plants deteriorated within 3-4 days.
Chapter Five: Environmental Orchestration
Sarah had learned that nutrition alone never guaranteed success—environmental control worked hand-in-hand with feeding programs to create optimal growing conditions.
Temperature Management:
The greenhouse thermostats maintained day temperatures at 68-75°F and night temperatures at 62-68°F. Sarah discovered that bok choy required this 6-10°F differential between day and night temperatures for optimal development. When temperatures exceeded 80°F, even perfect nutrition couldn’t prevent premature bolting.
Root zone temperature proved equally critical. Sarah’s chilled water systems maintained solution temperatures at 64-70°F, even during summer heat. Water temperatures above 75°F reduced oxygen solubility and created conditions favoring root diseases, regardless of nutrient levels.
Humidity and Air Movement:
Relative humidity between 65-75% provided optimal conditions for bok choy growth. Sarah’s environmental controls maintained this range through careful ventilation and evaporative cooling. Air movement of 0.5-1.0 mph prevented stagnant conditions while avoiding excessive transpiration that could stress plants.
Lighting Requirements:
Sarah’s LED systems delivered 16-20 mol/m²/day of photosynthetically active radiation, with photoperiods of 14-16 hours during vegetative growth. The spectrum combined 25% blue light (400-500nm) with 75% red light (600-700nm), optimizing both vegetative growth and nutritional content.
Light intensity at canopy level remained between 300-450 PPFD. Sarah had learned that excessive light intensity, even with perfect nutrition, created heat stress and reduced quality. The key was providing adequate light without overwhelming the plants’ ability to process it effectively.
Carbon Dioxide Supplementation:
Atmospheric CO₂ levels of 600-900 ppm during light periods enhanced growth rates by 20-25% when combined with optimal nutrition. Sarah’s CO₂ injection systems activated only during daylight hours, reducing to ambient levels during dark periods to prevent oxygen displacement.
Chapter Six: The Micronutrient Symphony
While macronutrients provided the foundation, micronutrients represented the fine-tuning that separated good bok choy from exceptional specimens. Sarah had developed specialized micronutrient programs that addressed bok choy’s specific requirements.
Iron Management:
Iron deficiency appeared quickly in hydroponic bok choy, creating interveinal chlorosis that destroyed visual appeal. Sarah used chelated iron (Fe-DTPA) at 3.0-4.5 ppm, maintaining this level throughout the growing cycle. pH stability was crucial—iron availability dropped dramatically above pH 6.5.
“Iron is like insurance,” Sarah explained to new growers. “You don’t see its value until it’s missing. Maintain 3 to 4.5 parts per million, and leaves stay deep green. Drop below 2 ppm, and you’ll see yellowing within a week.”
Manganese for Enzyme Function:
Manganese deficiency created subtle but devastating effects on bok choy quality. Sarah maintained 1.0-1.5 ppm manganese throughout the growing cycle, using manganese sulfate for immediate availability. Symptoms appeared as interveinal chlorosis on young leaves, often confused with iron deficiency.
Boron for Cell Wall Integrity:
Boron requirements increased during rapid growth phases. Sarah applied 0.4-0.6 ppm boron, crucial for proper cell wall formation and calcium transport. Boron deficiency created brittle leaves and hollow stems—problems that no amount of macronutrients could correct.
Zinc for Growth Regulation:
Zinc deficiency stunted growth and reduced leaf expansion. Sarah maintained 0.4-0.6 ppm zinc using zinc sulfate, particularly important during the vegetative growth phase when cell division occurred rapidly.
Molybdenum for Nitrogen Metabolism:
Often overlooked, molybdenum proved essential for nitrogen utilization. Sarah applied 0.06-0.10 ppm molybdenum, particularly important when using high nitrogen solutions. Deficiency created symptoms similar to nitrogen deficiency despite adequate nitrogen availability.
Chapter Seven: System Monitoring and Precision Management
Sarah’s daily routine began at 6 AM with comprehensive system monitoring. Success in hydroponic bok choy production demanded vigilance and precision that left no detail to chance.
Daily Monitoring Protocol:
pH measurements occurred twice daily using calibrated meters. Sarah targeted 6.0-6.2 for optimal nutrient availability, adjusting with phosphoric acid for reduction or potassium hydroxide for elevation. Daily pH drift of 0.2-0.4 units indicated healthy plant activity.
Electrical conductivity monitoring revealed plant consumption patterns. Rising EC indicated inadequate water uptake, while falling EC suggested heavy nutrient consumption. Sarah maintained target ranges throughout growth stages, replacing 20-30% of solution volume weekly.
Dissolved oxygen levels required constant attention. Sarah’s oxygen meters confirmed levels above 6 ppm throughout all growing areas. Oxygen depletion occurred rapidly in warm weather, requiring increased aeration or chilled water systems.
Root Health Assessment:
Daily root inspection revealed system health better than any meter. Healthy bok choy roots remained white to cream-colored with extensive branching. Brown or slimy roots indicated oxygen deficiency, disease, or nutrient imbalances requiring immediate correction.
Sarah had learned to recognize root health patterns. Excessive nitrogen created lush, dark green foliage but weak, brown roots susceptible to disease. Balanced nutrition produced moderate green foliage with robust, white root systems that efficiently absorbed nutrients.
Plant Monitoring Indicators:
Leaf color provided immediate feedback on nutritional status. Deep green leaves indicated adequate nitrogen, while pale green suggested deficiency. Purple leaf edges during cool weather indicated phosphorus limitations, while yellow margins suggested potassium deficiency.
Growth rate monitoring revealed system performance. Healthy bok choy plants increased fresh weight by 15-25% daily during peak growth phases. Slower growth rates indicated environmental stress, nutritional imbalances, or developing disease problems.
Chapter Eight: Problem Solving and Crisis Management
Even experienced growers faced challenges, and Sarah had developed systematic approaches to identifying and correcting problems before they became disasters.
Nutrient Deficiency Diagnosis:
Nitrogen Deficiency Pattern: Yellowing began with older leaves, progressing upward through the plant. Overall growth slowed, and plants appeared pale and stunted. Sarah’s treatment involved immediate application of calcium nitrate at 200-250 ppm nitrogen, followed by adjustment of base solution formulation.
Phosphorus Deficiency Recognition: Purple leaf edges and stems, particularly during cool weather, indicated phosphorus limitations. Stunted root development and delayed maturity accompanied visible symptoms. Treatment required increasing phosphorus levels to 50-65 ppm and ensuring pH remained below 6.5 for optimal availability.
Potassium Deficiency Symptoms: Brown leaf margins (marginal burn) beginning with older leaves indicated potassium deficiency. Weak stems and poor quality development followed. Sarah’s correction involved immediate potassium sulfate application bringing solution levels to 300-340 ppm potassium.
Calcium Deficiency Issues: Tip burn on young leaves, particularly during rapid growth phases, indicated calcium deficiency. This problem often resulted from environmental stress rather than low solution calcium levels. Treatment involved maintaining consistent solution temperature and adequate oxygen levels while increasing calcium to 220-240 ppm.
Environmental Stress Responses:
Temperature Stress Management: High temperatures above 80°F caused bolting regardless of nutrition levels. Sarah’s emergency protocols included shade cloth installation, increased air movement, and chilled water circulation. Nutrition adjustments included increased potassium for stress tolerance.
Light Stress Correction: Excessive light intensity created bleached leaves and reduced quality. Sarah adjusted LED intensity to maintain 300-450 PPFD at canopy level, particularly during summer months when ambient heat complicated light management.
Humidity Stress Prevention: Low humidity below 50% increased transpiration stress and calcium deficiency symptoms. Sarah’s humidification systems maintained 65-75% relative humidity, particularly important during winter months when heating systems reduced moisture levels.
Chapter Nine: Harvest Optimization and Quality Control
The culmination of six weeks of precise nutrition and environmental management arrived with harvest—the moment when Sarah’s efforts translated into premium bok choy that commanded top market prices.
Harvest Timing Indicators:
Visual assessment determined optimal harvest timing. Mature bok choy displayed thick, white stems 6-8 inches tall with deep green leaves extending 8-12 inches. The stem-to-leaf ratio provided quality indicators—thick stems with proportionate leaves indicated proper nutrition, while thin stems suggested potassium deficiency.
Harvest Technique:
Sarah harvested during early morning hours when plant tissues contained maximum moisture and minimum nitrate concentrations. Sharp knives cut plants at soil level, avoiding damage to delicate tissues that reduced storage life.
Post-harvest handling began immediately. Harvested bok choy was immersed in ice water within 30 minutes, rapidly reducing field heat and maintaining cellular integrity. Proper nutrition during growing, particularly adequate calcium, extended storage life from 5-7 days to 12-15 days under optimal conditions.
Quality Assessment Parameters:
Nutritional Quality: Well-fertilized bok choy contained elevated levels of vitamins A, C, and K, with mineral content reflecting hydroponic solution composition. Nitrate levels remained below 2,000 ppm fresh weight when nitrogen was properly managed during pre-harvest phases.
Physical Quality: Stem firmness provided immediate quality indicators. Properly fertilized bok choy produced stems that remained crisp and crunchy for 10-14 days post-harvest. Calcium-deficient plants showed soft, flexible stems within 2-3 days.
Storage Performance: Adequate calcium nutrition during growing translated directly to storage life. Sarah’s properly fertilized bok choy maintained market quality for 12-15 days at 32-35°F with 95% relative humidity, while nutritionally stressed plants deteriorated within a week.
Chapter Ten: Economic Analysis and Optimization
Sarah’s detailed record-keeping revealed the economic realities of hydroponic bok choy production, demonstrating how proper nutrition management directly impacted profitability.
Production Cost Analysis (per 100 sq ft):
- Seeds: $25-35
- Nutrients: $40-60
- Energy (lighting/climate): $80-120
- Growing media: $20-30
- Labor: $60-90
- Total costs: $225-335
Revenue Generation:
- Yield per 100 sq ft: 60-80 lbs per crop cycle
- Wholesale price: $4-7 per lb
- Retail price: $8-12 per lb
- Gross revenue: $240-960 per cycle
- Production cycles annually: 6-8
- Annual gross revenue: $1,440-7,680
Profit Optimization Strategies:
Precision nutrition represented 18-25% of total production costs but determined 70-85% of final yield and quality outcomes. Sarah’s data showed that premium nutrition programs increased costs by $15-20 per 100 square feet but improved yields by 25-40% while accessing higher-price market segments.
Market timing proved crucial. Sarah’s succession planting schedules maintained continuous harvest availability, commanding premium prices during supply gaps. Off-season production under optimal controlled conditions often generated 200-300% higher prices than field-grown alternatives.
Direct marketing to restaurants provided the highest returns. Sarah’s consistent quality and reliable supply schedules allowed her to negotiate contracts at $8-12 per pound compared to $4-6 wholesale prices.
Chapter Eleven: Advanced Production Techniques
Sarah’s success attracted attention from commercial growers seeking to replicate her results on larger scales. Her advanced techniques pushed the boundaries of hydroponic bok choy production.
Precision Fertigation Systems:
Automated dosing systems maintained exact nutrient concentrations throughout growing cycles. pH and EC controllers adjusted solution parameters every 15 minutes, maintaining optimal conditions regardless of environmental fluctuations.
Individual plant monitoring systems tracked uptake patterns and growth rates, enabling predictive adjustments before deficiencies appeared. This precision approach increased yields by 15-20% while reducing nutrient waste by 25-30%.
Multi-tier Production:
Vertical growing systems increased production capacity by 300-400% per square foot of floor space. Each growing level required individual environmental and nutritional management, with LED lighting and climate control optimized for canopy height and growth stage.
Sarah’s three-tier systems produced 180-240 lbs of bok choy per 100 square feet of floor space annually, compared to 60-80 lbs from single-level production.
Controlled Atmosphere Storage:
Post-harvest storage in controlled atmosphere conditions extended market life while maintaining quality. Reduced oxygen levels (2-4%) and elevated CO₂ (5-8%) slowed respiration and aging processes.
Combined with optimal pre-harvest nutrition, controlled atmosphere storage maintained bok choy quality for 21-28 days, enabling expanded market reach and higher prices through extended distribution windows.
Integrated Pest Management:
Beneficial insect releases and biological controls eliminated pesticide requirements while maintaining crop health. Predatory mites, parasitic wasps, and beneficial bacteria worked together to control pests and diseases naturally.
Proper nutrition enhanced plant resistance to pests and diseases. Adequate silica nutrition (50-75 ppm) strengthened cell walls, while balanced mineral nutrition improved natural defense mechanisms.
Chapter Twelve: Sustainability and Innovation
Sarah’s operation evolved beyond simple production to encompass sustainable practices that reduced environmental impact while maintaining economic viability.
Closed-Loop Nutrient Management:
Nutrient recycling systems captured and reprocessed drainage water, reducing waste by 90-95%. Automated monitoring maintained solution quality while minimizing fresh nutrient inputs.
Water consumption averaged 95% less than field production through recirculation and precise application. Sarah’s systems used 2-3 gallons per pound of bok choy compared to 25-40 gallons for field production.
Energy Efficiency Optimization:
LED lighting systems consumed 40-50% less energy than traditional lighting while providing superior light quality for plant growth. Smart environmental controls adjusted lighting, heating, and cooling based on real-time plant needs and weather conditions.
Thermal mass systems stored excess heat during sunny periods, reducing heating costs during cool weather. Combined with renewable energy sources, these systems achieved energy independence during peak production periods.
Waste Stream Utilization:
Plant residues and growing media were composted into soil amendments for local organic farmers. This closed-loop approach eliminated waste disposal costs while generating additional revenue streams.
Used nutrient solutions, after filtration and treatment, provided irrigation water for landscape applications, further reducing waste while conserving fresh water resources.
Epilogue: The Master Grower’s Reflection
As Sarah reviewed her production records from another successful season, she reflected on the journey from novice hydroponic enthusiast to recognized expert in bok choy cultivation. The numbers told an impressive story: 98% germination rates, 45-day seed-to-harvest cycles, yields averaging 1.2 pounds per square foot per crop, and premium prices that reflected the quality her precise nutrition management delivered.
But beyond the numbers lay the deeper satisfaction of mastering a complex agricultural system. Each perfectly formed bok choy represented countless decisions—from initial variety selection through harvest timing—all orchestrated through understanding of plant nutrition and environmental control.
Sarah’s students often asked for the “secret” to her success. She would smile and point to her detailed records: pH measurements taken twice daily for three years, nutrient solution analyses filed by date and growth stage, environmental data logged every hour. The secret wasn’t mysterious—it was methodical application of scientific principles combined with careful observation and continuous refinement.
“Hydroponic bok choy teaches you precision,” she would tell visitors to her facility. “Every nutrient matters. Every environmental parameter affects the outcome. But when you get it right—when those thick white stems and deep green leaves emerge from your systems—you know you’ve achieved something special.”
The future held new challenges: expanding production, training additional growers, developing new varieties optimized for hydroponic systems. But Sarah faced these challenges with confidence born from understanding. She had mastered the art and science of hydroponic bok choy production, and that knowledge would guide whatever agricultural adventures lay ahead.
In the quiet of the greenhouse after sunset, with pumps humming softly and LED lights casting their gentle glow across rows of perfect bok choy, Sarah found the peace that comes from work well done. Tomorrow would bring new measurements, new adjustments, new decisions—but tonight, she could rest in the satisfaction of crops growing precisely as planned, nourished by solutions crafted with the skill of a master grower.
The journey from seed to harvest continued, and Sarah Chen—hydroponic bok choy specialist—was ready for whatever challenges the next growing cycle might bring.
Author’s Note: This narrative represents real-world hydroponic production techniques developed through years of research and practical application. The nutrient formulations, environmental parameters, and production methods described have been proven effective in commercial operations. While presented as fiction, the technical content reflects current best practices in controlled environment agriculture.
