Horticulture

1. Introduction to Horticulture

The word Horticulture is derived from the Latin words Hortus (garden) and Cultura (cultivation). Tamil Nadu is one of India's leading horticultural states because of its diverse climate, irrigation facilities, and government support schemes. Horticulture contributes significantly to food security, nutrition, employment, export earnings, and rural development.

Importance of Horticulture

• Provides nutritious food rich in vitamins and minerals.
• Generates higher income compared to field crops.
• Creates employment throughout the year.
• Supports agro-processing industries.
• Promotes export of fruits, vegetables, flowers, and spices.
• Conserves biodiversity.
• Improves environmental quality through greenery.

Branches of Horticulture

• Pomology – Fruit science.
• Olericulture – Vegetable science.
• Floriculture – Flower cultivation.
• Plantation Crops – Coconut, Tea, Coffee, Rubber.
• Spices and Condiments.
• Medicinal and Aromatic Crops.
• Landscape Gardening.
• Post-Harvest Technology.

2. Classification of Horticultural Crops

Fruits

Examples: Mango, Banana, Guava, Sapota, Grapes, Citrus, Papaya, Pomegranate.

Vegetables

• Root Vegetables: Carrot, Radish, Beetroot.
• Tuber Vegetables: Potato, Sweet potato, Tapioca.
• Leafy Vegetables: Spinach, Amaranthus, Coriander.
• Fruit Vegetables: Tomato, Brinjal, Chilli, Okra, Pumpkin.
• Bulb Vegetables: Onion, Garlic.

Flowers

Rose, Jasmine, Marigold, Chrysanthemum, Tuberose, Crossandra, Orchid.

Spices

Pepper, Cardamom, Turmeric, Ginger, Coriander, Cumin, Fennel.

Plantation Crops

Coconut, Arecanut, Tea, Coffee, Cocoa, Rubber.

3. Climate and Soil Requirements

Climate is the most important factor influencing crop growth.

Climatic Factors

• Temperature: Controls flowering, fruiting and maturity.
• Rainfall: Adequate rainfall is essential for growth but excessive rainfall causes diseases.
• Humidity: High humidity favors fungal diseases.
• Light: Required for photosynthesis.
• Wind: Strong winds damage trees and flowers.

Soil

Ideal horticultural soil should possess good drainage, high fertility, organic matter, proper aeration, and suitable pH.

Soil Types

• Red Soil: Suitable for mango and groundnut.
• Black Soil: Suitable for cotton and vegetables.
• Alluvial Soil: Suitable for banana and vegetables.
• Laterite Soil: Suitable for tea and coffee.

Soil pH

• Acidic: Below 6.5
• Neutral: 6.5–7.5
• Alkaline: Above 7.5
• Most horticultural crops grow well at pH 6.0–7.5.

4. Propagation of Horticultural Crops

Propagation means multiplication of plants. There are two methods.

A. Sexual Propagation

Done through seeds.

Advantages

• Simple, Economical, Deep-rooted plants, Used for rootstock production.

Disadvantages

• Variation among seedlings, Late bearing, Non-uniform crop.

Examples

Papaya, Coconut, Arecanut.

B. Asexual (Vegetative) Propagation

Plants are multiplied using vegetative parts.

Advantages

• True-to-type plants, Early bearing, Uniform crop, Better quality fruits.

Methods

• Cutting: Stem or root pieces are planted. Examples: Rose, Bougainvillea, Grapes.
• Layering: Types – Simple layering, Air layering, Mound layering. Examples: Jasmine, Guava, Litchi.
• Grafting: Joining scion and rootstock. Types – Veneer grafting, Softwood grafting, Cleft grafting, Approach grafting. Examples: Mango, Sapota.
• Budding: A single bud is inserted into stock. Examples: Rose, Citrus.
• Tissue Culture: Micropropagation under sterile laboratory conditions. Advantages – Rapid multiplication, Disease-free plants, Uniform growth, Year-round production. Examples: Banana, Orchid, Potato.

5. Nursery Management

A nursery is a place where young plants are produced.

Objectives

• Healthy seedlings, Uniform planting material, Disease-free plants.

Characteristics of Good Nursery

• Fertile soil, Irrigation facility, Good drainage, Fencing, Shade, Road access.

Nursery Operations

• Seed treatment, Bed preparation, Sowing, Watering, Weeding, Fertilizer application, Plant protection, Hardening, Transplanting.

6. Orchard Establishment

An orchard is an area where fruit trees are cultivated.

Steps

• Site selection, Land preparation, Layout, Pit digging, Filling pits, Planting, Irrigation, Training, Pruning, Plant protection.

Systems of Planting

• Square System: Most common. Advantages – Easy irrigation, Easy intercultural operations.
• Rectangular System: Distance between rows differs from plants.
• Triangular System: More plants than square.
• Hexagonal System: Maximum land utilization.
• Quincunx System: Temporary filler crop planted.

7. Manures and Fertilizers

Organic Manures

• Farmyard Manure (FYM): Prepared from cattle dung and urine. Benefits – Improves soil fertility, Enhances microbial activity, Improves water holding capacity.
• Compost: Prepared from organic wastes.
• Vermicompost: Produced by earthworms. Advantages – Rich in nutrients, Improves soil structure, Environment friendly.
• Green Manure: Plants incorporated into soil before flowering. Examples – Sunnhemp, Dhaincha.

Chemical Fertilizers

Nitrogen (N)

• Functions: Vegetative growth, Leaf development.
• Deficiency: Yellow leaves, Poor growth.
• Sources: Urea, Ammonium sulphate.

Phosphorus (P)

• Functions: Root growth, Flowering, Seed formation.
• Deficiency: Purple leaves, Weak roots.
• Sources: SSP, DAP.

Potassium (K)

• Functions: Fruit quality, Disease resistance, Water regulation.
• Deficiency: Leaf scorching, Poor fruit quality.
• Sources: MOP, SOP.

8. Irrigation

Water is essential for crop growth.

Methods

• Surface Irrigation: Basin, Furrow, Flood.
• Sprinkler Irrigation: Suitable for vegetables and lawns. Advantages – Uniform watering, Saves labour.
• Drip Irrigation: Most efficient irrigation system. Advantages – Saves 40–70% water, Reduces weed growth, Higher yield, Fertigation possible, Suitable for orchards.

9. Weed Management

Weeds compete with crops.

Losses

• Reduce yield, Harbor pests, Harbor diseases, Increase cultivation cost.

Methods

• Cultural: Crop rotation, Mulching.
• Mechanical: Hand weeding, Hoeing.
• Chemical: Use herbicides. Examples – Glyphosate, Pendimethalin, Atrazine.

10. Plant Growth Regulators (PGRs)

Plant hormones regulate growth.

• Auxins: Functions – Root initiation, Prevent fruit drop. Examples – IAA, IBA, NAA.
• Gibberellins: Functions – Stem elongation, Increase fruit size, Break seed dormancy. Example – GA₃.
• Cytokinins: Functions – Cell division, Delay leaf senescence.
• Ethylene: Functions – Fruit ripening, Flower induction in pineapple. Commercial source – Ethephon.
• Abscisic Acid: Functions – Dormancy, Stomatal closure, Stress tolerance.

11. Training and Pruning

Training is directing plant growth. Objectives – Strong framework, Better sunlight, Easy harvesting. Methods – Open centre, Central leader, Modified leader.

Pruning is removal of unwanted branches. Advantages – Better flowering, Better fruit quality, Disease control, Easy spraying, Increased yield.

12. Mulching

Mulching means covering soil around plants.

Materials

• Straw, Dry leaves, Plastic mulch, Sugarcane trash.

Advantages

• Conserves moisture, Controls weeds, Maintains soil temperature, Reduces erosion, Improves yield.

13. Intercropping and Cropping Systems

Intercropping is growing two or more crops together.

Advantages

• Better land use, Additional income, Weed suppression, Risk reduction.

Examples

• Coconut + Banana, Mango + Vegetables, Coconut + Cocoa, Coconut + Pepper.

14. Protected Cultivation

Growing crops under controlled environment.

Structures

• Greenhouse, Shade net house, Polyhouse, Low tunnel.

Advantages

• Higher yield, Better quality, Off-season cultivation, Reduced pest incidence, Efficient water use.

Suitable Crops

• Capsicum, Tomato, Cucumber, Gerbera, Carnation, Rose.

15. Organic Horticulture

Organic farming avoids synthetic chemicals.

Principles

• Soil health, Biodiversity conservation, Ecological balance, Sustainable production.

Inputs

• FYM, Vermicompost, Neem cake, Panchagavya, Jeevamrutham, Biofertilizers, Biopesticides.

Benefits

• Safe food, Better soil fertility, Environmental protection, Premium market price.

Important One-Liners for TNPSC CTS

• Father of Horticulture – Liberty Hyde Bailey.
• Father of Indian Horticulture – Dr. M. H. Marigowda.
• Pomology – Fruit science; Olericulture – Vegetable science; Floriculture – Flower science.
• Drip irrigation saves maximum water.
• Tissue culture produces disease-free plants.
• Mango is the National Fruit of India.
• Banana is propagated mainly through suckers and tissue culture.
• Rose is commonly propagated by budding.
• Grapes are propagated by stem cuttings.
• Mango is commonly propagated by veneer grafting.
• Ethephon is used for artificial fruit ripening.
• GA₃ promotes stem elongation.
• Auxins promote root initiation; Cytokinins promote cell division; Ethylene promotes fruit ripening.
• Vermicompost is prepared using earthworms.
• Mulching conserves soil moisture.
• Square system is the most common orchard planting system.
• Drip irrigation is ideal for orchards.
• Protected cultivation is widely used for high-value vegetables and flowers.

16. Fruit Science (Pomology)

Pomology is the branch of horticulture dealing with the cultivation, improvement, production, harvesting, storage, processing, and marketing of fruit crops. Fruits are rich in carbohydrates, vitamins, minerals, antioxidants, and dietary fibre.

Classification of Fruits Based on Climate

• Tropical Fruits: Grow well in warm climates and are sensitive to frost. Examples – Mango, Banana, Papaya, Sapota, Pineapple, Jackfruit.
• Subtropical Fruits: Require mild winter. Examples – Citrus, Guava, Pomegranate, Fig, Litchi.
• Temperate Fruits: Require chilling hours. Examples – Apple, Pear, Peach, Plum, Cherry, Strawberry.

Mango (King of Fruits)

• Scientific Name: Mangifera indica; Family: Anacardiaceae.
• Climate: Warm tropical climate; Soil: Well-drained loamy soil.
• Propagation: Mainly veneer grafting and softwood grafting.
• Popular Varieties: Alphonso, Banganapalli, Neelum, Imam Pasand, Malgoa, Totapuri.
• Major Problems: Mango hopper, Fruit fly, Powdery mildew, Anthracnose.
• Uses: Fresh fruit, Pickles, Juice, Pulp, Jam.

Banana (Queen of Fruits in India)

• Scientific Name: Musa paradisiaca; Family: Musaceae.
• Propagation: Suckers and tissue culture.
• Major Varieties: Grand Naine, Poovan, Rasthali, Monthan, Robusta, Nendran.
• Importance: Rich in potassium, Available throughout the year, Major export crop.
• Diseases: Panama wilt, Sigatoka leaf spot, Bunchy top virus.

Guava

• Scientific Name: Psidium guajava; Propagation: Air layering and grafting.
• Varieties: Allahabad Safeda, Lucknow-49, Arka Mridula.
• Rich in Vitamin C.

Papaya

• Scientific Name: Carica papaya; Propagation: Seeds.
• Important Facts: Dioecious plant, Rich in Vitamin A, Contains Papain enzyme.
• Diseases: Papaya Ring Spot Virus, Foot rot.

Citrus

• Includes: Orange, Lemon, Lime, Mandarin.
• Propagation: Budding; Disease: Citrus canker.

Grapes

• Propagation: Stem cuttings.
• Major Diseases: Downy mildew, Powdery mildew.
• Uses: Fresh fruit, Raisins, Wine, Juice.

17. Vegetable Science (Olericulture)

Vegetables are protective foods containing vitamins, minerals and fibre.

Tomato

• Scientific Name: Solanum lycopersicum; Family: Solanaceae; Propagation: Seeds.
• Major Diseases: Early blight, Late blight, Leaf curl virus.
• Uses: Salad, Sauce, Ketchup, Juice.

Brinjal

• Scientific Name: Solanum melongena; Propagation: Seeds.
• Major Pest: Shoot and fruit borer.

Chilli

• Scientific Name: Capsicum annuum.
• Uses: Spice, Vegetable, Pickle; Disease: Leaf curl virus.

Okra

• Scientific Name: Abelmoschus esculentus.
• Major Pest: Fruit borer; Disease: Yellow Vein Mosaic Virus.

Onion

• Scientific Name: Allium cepa; Propagation: Seeds.
• Importance: Rich in antioxidants; Storage: Requires proper ventilation.

Potato

• Scientific Name: Solanum tuberosum; Propagation: Seed tubers; Disease: Late blight.

Cabbage & Cauliflower

• Cabbage – Major Pest: Diamondback moth.
• Cauliflower – Requires cool climate.

Cucurbits

• Examples: Pumpkin, Bottle gourd, Bitter gourd, Snake gourd, Ridge gourd, Cucumber.
• Pollination: Mostly by insects.

18. Floriculture

Floriculture deals with commercial cultivation of flowers.

Importance

• Decoration, Religious purposes, Landscaping, Export, Perfume industry.

Rose

• Propagation: Budding. Uses: Cut flowers, Rose oil, Perfume, Rose water.

Jasmine

• Tamil Nadu is a leading producer. Propagation: Layering and cuttings.
• Uses: Garland, Perfume, Essential oil.

Marigold

• Propagation: Seeds. Uses: Decoration, Religious purposes, Nematode management.

Chrysanthemum

• Propagation: Suckers and cuttings.

Tuberose

• Propagation: Bulbs. Uses: Perfume industry.

Orchid

• High-value flower. Propagation: Tissue culture.

19. Plantation Crops

Coconut

• Scientific Name: Cocos nucifera; Propagation: Seeds.
• Products: Tender coconut, Copra, Coconut oil, Coir, Coconut shell products.
• Major Pest: Rhinoceros beetle; Disease: Bud rot.

Arecanut

• Used for chewing purposes. Propagation: Seeds.

Tea

• Scientific Name: Camellia sinensis; Climate: Cool humid climate.
• Major Producing Areas in Tamil Nadu: Nilgiris, Valparai.

Coffee

• Species: Arabica, Robusta. Shade-loving crop.
• Major Pest: Coffee berry borer.

Cocoa

• Often grown as intercrop in coconut plantations.

20. Spices and Condiments

Black Pepper

• King of Spices. Propagation: Cuttings. Produces spikes containing pepper berries.

Cardamom

• Queen of Spices. Climate: Humid hills. Propagation: Seeds and suckers.

Turmeric

• Propagation: Rhizomes. Contains Curcumin pigment. Uses: Spice, Medicine, Dye.

Ginger

• Propagation: Rhizomes. Used in food and medicine.

Coriander

• Propagation: Seeds. Leaves and seeds are used.

21. Medicinal and Aromatic Plants

Medicinal Plants

Aloe vera, Ashwagandha, Tulsi, Senna, Neem, Amla.

Aromatic Plants

Lemongrass, Citronella, Mint, Vetiver, Palmarosa.

Importance

• Pharmaceutical industry, Cosmetics, Essential oils, Export.

22. Plant Protection

Plant protection includes management of insects, diseases and nematodes.

Types of Pests

• Chewing Insects: Caterpillars, Beetles.
• Sucking Insects: Aphids, Whiteflies, Thrips, Mealybugs.

Diseases

• Fungal Diseases: Powdery mildew, Downy mildew, Wilt, Anthracnose.
• Bacterial Diseases: Citrus canker, Bacterial wilt.
• Viral Diseases: Leaf curl, Mosaic, Yellow vein mosaic, Bunchy top.

Integrated Pest Management (IPM)

• Principles: Resistant varieties, Healthy seedlings, Crop rotation, Field sanitation, Biological control, Need-based pesticide application.
• Advantages: Less pollution, Lower pesticide residues, Sustainable farming, Higher profitability.

Biological Control Agents

• Trichoderma, Pseudomonas fluorescens, Bacillus subtilis, Ladybird beetle, Chrysoperla.

23. Biofertilizers

Biofertilizers contain beneficial microorganisms.

Examples

• Azospirillum, Azotobacter, Rhizobium, Phosphate Solubilizing Bacteria (PSB), VAM.

Benefits

• Improve nutrient availability, Reduce fertilizer use, Improve soil fertility, Increase yield.

24. Post-Harvest Technology

Post-harvest losses in horticultural crops are high because of perishability.

Operations

• Harvesting, Cleaning, Grading, Sorting, Packing, Storage, Transportation, Marketing.

Importance

• Reduces losses, Improves shelf life, Better prices, Export quality.

Storage

• Cold storage is suitable for fruits, vegetables and flowers. Advantages – Reduces spoilage, Maintains quality, Extends shelf life.

Value Addition

• Mango pulp, Tomato ketchup, Banana chips, Pickles, Jam, Jelly, Squash, Dehydrated vegetables.

25. Landscape Gardening

Landscape gardening combines art and science.

Objectives

• Beautification, Recreation, Pollution reduction, Environmental protection.

Components

• Lawns, Hedges, Shrubs, Trees, Fountains, Rock gardens, Avenue planting.

26. Precision Horticulture

Uses modern technologies.

Components

• GPS, GIS, Drones, Sensors, Drip irrigation, Fertigation.

Benefits

• Saves water, Increases yield, Reduces production cost, Improves fertilizer efficiency.

27. Government Schemes (Important for TNPSC)

• Mission for Integrated Development of Horticulture (MIDH).
• National Horticulture Mission (NHM).
• Pradhan Mantri Krishi Sinchayee Yojana (PMKSY).
• Paramparagat Krishi Vikas Yojana (PKVY).
• Rashtriya Krishi Vikas Yojana (RKVY).
• Micro Irrigation Scheme.
• Integrated Horticulture Development Scheme (Tamil Nadu).

Objectives

• Area expansion, Quality planting materials, Protected cultivation, Post-harvest management, Farmer income enhancement.

28. Important Research Institutes

• ICAR – Indian Institute of Horticultural Research (IIHR), Bengaluru.
• ICAR – Central Institute for Subtropical Horticulture, Lucknow.
• ICAR – Central Plantation Crops Research Institute (CPCRI), Kasaragod.
• ICAR – Indian Institute of Vegetable Research (IIVR), Varanasi.
• ICAR – Indian Institute of Spices Research (IISR), Kozhikode.
• Tamil Nadu Agricultural University (TNAU), Coimbatore.
• Horticultural College and Research Institute, Periyakulam.

TNPSC Important Facts

• Mango – King of Fruits; Black Pepper – King of Spices; Cardamom – Queen of Spices.
• Banana is propagated by suckers and tissue culture.
• Rose is propagated by budding.
• Jasmine is propagated by layering.
• Grapes are propagated by cuttings.
• Mango is commonly propagated by veneer grafting.
• Papaya contains papain enzyme.
• Turmeric contains curcumin.
• Drip irrigation is most suitable for orchards.
• Tissue culture produces disease-free planting materials.
• Trichoderma is a beneficial fungus used in disease management.
• Rhizobium fixes atmospheric nitrogen in legumes.
• Azospirillum is widely used in horticultural crops.
• Cold storage reduces post-harvest losses.
• Protected cultivation is ideal for high-value vegetables and flowers.
• Tamil Nadu Agricultural University (TNAU) is the premier agricultural university in Tamil Nadu.
• Nilgiris is famous for tea cultivation.
• Coconut is called the "Tree of Heaven" or "Kalpavriksha" due to its multiple uses.
• India is one of the world's largest producers of fruits and vegetables.
• Horticulture contributes significantly to nutritional security, employment, exports, and farmers' income.