Hydroponic Culinary Herb Production

Culinary Herb Production in Hydroponics

• Culinary herbs are a valuable crop for hydroponic systems, offering a "one-stop shop" solution for produce buyers.
• They can be a profitable alternative to poinsettias during the holiday season.
• Popular herbs include basil, parsley, chives, dill, mint, thyme, rosemary, French tarragon, oregano, sage, sweet marjoram, French sorrel, chervil, and cilantro.
• Herbs can be annuals or perennials, differing in propagation, growth rate, longevity, and growth habit.

Cultivar Selection

• Cultivar selection is crucial for increasing yields in greenhouses.
• Many herb species have numerous cultivars, while others have fewer.
• Commercially available varieties are often bred for field production.
• Consult growers, seed companies, and researchers for cultivar recommendations.
• Conduct trials to determine the best performers.

Propagation

• Herbs can be propagated through seeds or vegetatively (stem-tip cuttings).
• Annuals are usually propagated by seed, while perennials often use vegetative propagation.
• Seed propagation is relatively easy and inexpensive, requiring minimal specialized facilities.
• Factors to consider for seed propagation include substrate preparation, light conditions, temperature, and mineral nutrition. Seedlings generally are ready in 2-3 weeks.
• Vegetative propagation (cuttings) may be necessary for certain varieties like rosemary, sage, and lavender. Factors for successful cuttings include rooting hormones, humidity, substrate temperature, and mineral nutrition. Cuttings usually root in 3-5 weeks.

Production Systems

• NFT (Nutrient Film Technique) and DFT (Deep Flow Technique) are suitable hydroponic systems for herbs.
• Research suggests no significant difference in herb growth between these systems.
• System selection should prioritize operational factors like ease of maintenance and ergonomics.

Slow-Growing Herbs

• Some herbs, like purple basil, grow slowly.
• Multi-seeding within propagation cubes can increase planting density for these herbs but isn't always necessary.

Environmental Factors

• pH: Herb pH requirements vary (low, moderate, or high). Choosing a pH depends on the specific crops. Recommended pH values for various herbs are discussed elsewhere in the text.
• Electrical Conductivity (EC): EC levels for herb production depend on factors like life cycle, growth stage, greenhouse environment, oil/flavor production, and harvesting schedule. Recommended EC values for specific herbs are provided elsewhere.
• Temperature: Temperature influences growth rate and development. Suitable temperature ranges vary by herb. Cool-growing herbs are 50-60°F, moderate are 60-70°F, and warm are 70°F+.
• Light: The quantity of photosynthetic light is crucial for herb yield. Supplemental lighting, especially high-pressure sodium (HPS) lamps or LEDs (with blue light for enhanced flavor), can increase light levels. Photoperiod is generally not managed for herbs.

Postharvest

• Postharvest handling should mirror practices for leafy greens.
• Many herbs can be stored cold (32-40°F), but basil should never be stored below 50°F.

Maximizing Yield

• Focus on providing ideal conditions for growth.
• Regular monitoring of environmental factors and nutrient solutions is crucial. Factors discussed include new leaves (temperature), expansion of leaves (light), and healthy appearance (mineral nutrition).