HORMI - 202
Production Technology of Cut Flowers
Production Technology of Cut Flowers
UNIT II
📚 Contents
🌿 1. Growing Environment
The growing environment is a combination of all physical and biological factors influencing plant growth and flower quality.
✅ Key Components:
- Climatic Factors: Light, temperature, humidity, rainfall, wind
- Soil & Media Conditions: Fertility, drainage, structure
- Water Quality & Irrigation
- Protection from biotic and abiotic stresses
✅ Ideal Conditions for Cut Flowers:
| Parameter | Ideal Range |
|---|---|
| Light | 12–16 hrs/day (varies by crop) |
| Temperature | 20–28°C (day), 12–18°C (night) |
| Relative Humidity | 60–80% |
| Soil pH | 6.0–7.0 |
| EC (Electrical Conductivity) | < 1 dS/m for most species |
🌱 2. Open Cultivation
✅ Definition: Open cultivation refers to growing cut flowers in natural, open-field conditions, without any protective structures.
✅ Advantages:
- Low initial investment
- Large-scale cultivation possible
- Easy to manage in regions with suitable climates
✅ Disadvantages:
- Highly susceptible to weather fluctuations
- Pest and disease pressure is higher
- Flower quality and yield may be inconsistent
✅ Suitable Crops:
- Marigold, Aster, Gladiolus, Tuberose, Chrysanthemum, etc.
✅ Practices in Open Cultivation:
- Raised beds in heavy rainfall areas
- Windbreaks to reduce physical damage
- Seasonal sowing aligned with regional climate
- Field sanitation and crop rotation to manage pests/diseases
🏠 3. Protected Cultivation
✅ Definition:
Protected cultivation is the growing of high-value crops under controlled environments, using structures like greenhouses, polyhouses, net houses, or shade houses.
✅ Objectives:
- Enhance yield and quality
- Enable off-season and round-the-year production
- Protect crops from extreme weather and pests
✅ Structures Used:
| Structure | Features |
|---|---|
| Polyhouse | UV-stabilized plastic; semi-controlled climate |
| Greenhouse | Fully climate-controlled (temp, humidity, CO₂) |
| Net House | Covered with insect-proof net; better airflow |
| Shade House | Used to reduce light intensity (for shade-loving crops) |
✅ Key Components:
- Irrigation system: drip or mist
- Ventilation system: natural or forced
- Environmental sensors and control panels
- Growing benches or beds
✅ Benefits:
- Uniform quality flowers
- Reduced disease incidence
- Efficient use of inputs
- Longer vase life and better export potential
✅ Suitable Crops:
- Rose, Gerbera, Carnation, Anthurium, Lilium, Orchid, etc.
🌍 4. Soil Requirements
Soil plays a fundamental role in providing anchorage, nutrients, water, and aeration to the cut flower plants.
✅ Ideal Soil Characteristics for Cut Flowers:
| Property | Optimal Range |
|---|---|
| Texture | Sandy loam / loam (well-drained) |
| Structure | Crumbly with good tilth |
| pH | 6.0–7.0 (neutral to slightly acidic) |
| EC | < 1 dS/m |
| Organic Matter | High (well-decomposed FYM or compost) |
| Drainage | Excellent, with no waterlogging |
✅ Additional Recommendations:
- Incorporate 20–25 tonnes/ha of FYM or compost before planting.
- For loose, porous soil: add cocopeat or leaf mould.
- In heavy soils: use sand or vermiculite to improve aeration.
🧪 5. Artificial Growing Media
Artificial (soilless) media are used especially in protected cultivation to avoid soil-borne diseases and maintain better control over plant nutrition and moisture.
✅ Common Artificial Media:
| Medium | Properties |
|---|---|
| Cocopeat | Excellent water holding, biodegradable, pH 5.5–6.5 |
| Perlite | Volcanic glass, provides aeration, inert |
| Vermiculite | Good moisture retention and cation exchange |
| Rockwool | Sterile, uniform, used in hydroponics |
| Peat Moss | High water retention, low nutrient content |
| Sand | Improves drainage when mixed with other media |
✅ Ideal Media Mix:
- Cocopeat:Perlite:Vermiculite (3:1:1) – common in nurseries
- Peat:Perlite (1:1 or 2:1) – for seed germination and cuttings
✅ Advantages of Artificial Media:
- Better aeration and moisture balance
- Pathogen-free environment
- Consistent root development
- Lightweight and easy to handle
🔬 6. Soil Decontamination Techniques
Soil sterilization or decontamination is vital before planting high-value cut flowers to control pathogens, nematodes, and weed seeds.
✅ Methods:
- Solarization:
Cover moist soil with transparent polyethylene sheets during hot summer months for 4–6 weeks.
Solar heat kills pathogens, weed seeds, and nematodes.
Cost-effective and eco-friendly. - Chemical Treatment:
Formalin (2–5%) – effective for bacteria, fungi, and nematodes. Treated soil should be covered and left for 7–10 days.
Methyl bromide – once widely used, now banned in many countries.
Chloropicrin, Dazomet, and Basamid – used where legal and necessary. - Steam Sterilization:
Used in greenhouses/nurseries.
Soil is steamed at 80–100°C for 30–60 minutes to kill pathogens.
Leaves no chemical residue. - Biological Methods:
Use of antagonistic microbes (e.g., Trichoderma, Pseudomonas fluorescens).
Improves soil health over time.
🌱 7. Planting Methods
The method of planting cut flowers greatly affects growth, flower yield, and quality. It varies depending on the crop type, cultivation method (open/protected), and growing media.
✅ Factors to Consider:
- Spacing and plant population
- Root depth and spread
- Irrigation method (drip preferred)
- Support structures (nets or stakes for tall crops)
✅ Common Methods:
| Method | Suitable For | Description |
|---|---|---|
| Direct Sowing | Marigold, Aster | Seeds are sown directly in prepared beds |
| Transplanting | Carnation, Gerbera, Chrysanthemum | Seedlings or rooted cuttings are transplanted |
| Bulb Planting | Gladiolus, Lilium, Tuberose | Corms or bulbs are planted at specific depths |
| Tissue Culture Plants | Orchids, Gerbera | Hardened in nursery, then planted in protected structures |
✅ Depth & Spacing Examples:
| Crop | Depth | Spacing (cm) |
|---|---|---|
| Gladiolus | 6–8 cm | 20 x 10 |
| Marigold | 1.5–2 cm | 30 x 30 |
| Rose | Rootball depth | 60 x 45 |
| Gerbera | Crown just above soil | 30 x 30 |
🌡️ 8. Influence of Environmental Parameters
Environmental parameters significantly regulate physiological processes such as photosynthesis, respiration, flower induction, and pigmentation.
✅ Key Parameters:
- Light intensity & duration
- Temperature
- Humidity
- Soil and air moisture
- CO₂ concentration
- Air circulation
Each of these must be kept within the optimal range for best results, especially in protected cultivation.
☀️ 9. Light
Light influences photosynthesis, growth habit, flower initiation, color, and stem strength.
✅ Types of Light Effects:
- Photoperiodism: Flowering response to day length (Short-day vs. Long-day plants)
- Light Intensity: Affects biomass and stem length
- Light Quality: Blue and red spectrum light influence growth and flowering
✅ Photoperiod Classification:
| Crop | Type | Light Requirement |
|---|---|---|
| Chrysanthemum | Short-day | <12 day="" hours="" td=""> |
| Carnation | Long-day | >14 hours/day |
| Rose | Day-neutral | 12–16 hours/day |
✅ Supplemental Lighting:
- Fluorescent or LED lamps used in greenhouses
- Useful during cloudy seasons or winter
✅ Light Intensity (Lux) for Common Crops:
| Crop | Optimal Light (Lux) |
|---|---|
| Rose | 50,000–70,000 |
| Gerbera | 40,000–60,000 |
| Anthurium | 20,000–30,000 |
🌡️ 10. Temperature
Temperature is a key factor influencing vegetative growth, flower initiation, flower quality, and post-harvest life.
✅ Effects of Temperature:
- High temperature: Increases respiration, reduces flower size and longevity
- Low temperature: Delays flowering, can cause bud abortion
- Night temperature is critical for flower initiation in crops like chrysanthemum and carnation
✅ Optimal Temperature Ranges for Common Cut Flowers:
| Crop | Day Temp (°C) | Night Temp (°C) |
|---|---|---|
| Rose | 22–26 | 15–18 |
| Gerbera | 23–27 | 12–14 |
| Carnation | 18–24 | 10–12 |
| Gladiolus | 20–25 | 10–15 |
| Chrysanthemum | 20–25 | 15–18 |
✅ Temperature Control in Greenhouses:
- Fogging/misting and shading for cooling
- Heaters or poly tunnels for warming
- Proper ventilation to avoid heat build-up
💧 11. Moisture
Water is essential for nutrient transport, cell turgidity, photosynthesis, and flower quality.
✅ Effects of Moisture:
- Deficiency: Leads to reduced stem elongation, flower drop, poor color
- Excess: Causes root rot, fungal diseases, and poor oxygen availability
✅ Moisture Management:
- Maintain uniform soil moisture (neither too wet nor too dry)
- Use mulching to reduce evaporation
- Adopt drip irrigation for water-use efficiency
✅ Critical Stages for Moisture:
- Transplanting
- Bud initiation
- Flower development
💦 12. Humidity
Relative Humidity (RH) affects transpiration, disease incidence, and flower opening.
✅ Optimal RH for Cut Flowers:
- 60–70% RH during active growth
- 50–60% RH during flowering and harvesting
✅ Effects:
- Low RH: Causes excessive transpiration, wilting, and poor flower opening
- High RH: Promotes fungal diseases (Botrytis, powdery mildew)
✅ Control Measures:
- Foggers/misters to increase RH
- Ventilation, fans, and dehumidifiers to reduce RH
- Avoid overhead irrigation in high RH conditions
🫁 13. CO₂
Carbon dioxide is a limiting factor in photosynthesis, especially in protected environments.
✅ Optimal CO₂ Level:
600–1000 ppm (vs ambient ~400 ppm)
✅ Benefits of CO₂ Enrichment:
- Enhances biomass production
- Increases flower number and size
- Improves bud initiation and stem strength
✅ CO₂ Enrichment Methods:
- CO₂ generators (burning propane/natural gas)
- Compressed CO₂ cylinders with regulators
- Should be used only during daytime and in sealed greenhouses
✅ Caution:
- Above 1200 ppm may cause leaf scorch or ethylene production
- Proper monitoring is essential using CO₂ sensors