Introduction to protected cultivation of vegetables and other produce
Protected cultivation is a process of growing plants in a controlled environment. This means that the temperature, humidity, light, and other factors can be regulated as per the requirement of the crop. Then, this assists in healthier and larger produce. There are several types of protected cultivation practices. Some of the used practices are forced ventilated greenhouse, naturally ventilated Polyhouse, insect-proof net house, shade net house, plastic tunnel, and mulching, raised beds, trellising, and drip irrigation. These practices can be used independently or in combination, to provide a favorable environment to save plants from the harsh climate and extend the duration of crop cultivation or off-season crop production. Adoption of drip irrigation system under raised beds covered with mulch films not only eradicates weeds but also maintains moisture in the soil for a prolonged period by minimizing evaporation losses.
A guide to protected cultivation of vegetables, fruits, and flowers
It is defined as cropping techniques wherein the microclimate surrounding the plant body is controlled partially or fully, as per the requirement of the plant species. The various types of protective cultivation practices have been adopting based upon the prevailing climatic condition. Among them, Greenhouse or Polyhouse is extremely useful for Round-the-year vegetable cultivation in temperate conditions. Protected cultivation is also known as controlled environment agriculture (CEA) is highly productive, conservative of water and land, and also protective of the environment.
The difference between protected cultivation and open cultivation is;
Protected cultivation was found to be better than open cultivation in terms of total crop production. The average annual yield under the plastic greenhouse was about 53% higher than in the open field (65.5 t/ha compared with 42.8 t/ha).
The main components of protected cultivation structure are frame, cladding material, and ventilation/climate control systems. The frame needs to be constructed strong enough to sustain against different types of damaging factors such as wind, rain/snow, soil / climatic moisture, physical and chemical deterioration, etc. The cladding material must be transparent enough to provide required photosynthetically active radiation (PAR), entrap enough heat during cold weather, and protect the plants from outside conditions. The ventilation/climate control system must be designed to provide congenial climatic conditions for better plant performance with a reasonable compromise. Problems in protected cultivation are Low price of the product and lack of adequate market also the other problems with vegetable production. Inadequate government support in term of training and financial support to farmers in certain areas make it difficult in protected cultivation.
The advantages of protected cultivation are;
- Higher productivity resulting in increased crop yield.
- Provides a better growing environment for plants.
- Protects from rain, wind, high temperatures and minimizes the damage of insect pests and diseases thereby improving the quality and crop yield.
- Facilitates year-round production coupled with yield enhancement by 2 to 3 times compared to open cultivation.
- High water productivity and saving significant amounts of water.
- Significant reduction in pesticide use for lower production costs and healthier crop produce.
- Year-round crop production, allowing farmers to take advantage of market seasonality and higher prices.
- The crop grows healthier, uniform quality fruits and matures fast.
- Fertilizer use efficiency increases by 30% and the cost of fertilizers, inter-culturing, and labor use get reduced.
Objectives of protected cultivation of vegetables, fruits, herbs, and flowers
- Protection of plants from abiotic stress (physical or by the non-living organism) such as temperature, excess or deficit water, hot and cold waves, and biotic factors such as pest and disease incidences, etc.
- Efficient water use with minimum weed infestation.
- Enhancing productivity per unit area.
- Minimizing the use of pesticides in crop production.
- Promotion of high value, quality horticultural produce.
- Propagation of planting material to improve seed germination percentage; healthy, uniform, disease-free planting material, and better hardening.
- Year-round and off-season production of flower, vegetable, and fruit crops.
- Production of disease-free and genetically better transplants.
At present in India, the small and medium farmers have started flower and vegetable cultivation under different kinds of modular protected structures depending upon their investment capacity and availability of the market in their area. Among all the protected cultivation practices, greenhouse farming cultivation provides maximum benefits.
Why protected cultivation is preferred for vegetables, flowers, fruits, and herbs
The scope and importance of protected cultivation is;
The open-field production of vegetable encounters with many production constraints such as heavy rain, thunderstorms, excessive solar radiation, temperatures and humidity levels above plant growth optima, high insect pest infestation pressure, and fungal diseases. The environment is the most determinate factor in horticultural crop and protected cultivation is being used to control the effect of environmental effect. It is a sustainable approach toward vegetable production under adverse climate. Besides, from protection to adverse climatic conditions, the vegetable under protected cultivation yields high-quality vegetables in terms of shape, size, and colors. The microclimate can be changed inside the poly house and certain insects need UV light their vision purpose, the UV opaque covering material for poly house helps to restrict the insect to enter the house. Thus, there is minimum use of an insecticide. The production of vegetables is higher than the open field condition due to congenital inside microclimate and provided a better price. Protected cultivation comprises different devices and technologies such as windbreaks, and irrigation soil mulches, etc, and the structures which are a greenhouse, tunnel, row covers made the production throughout the year by modifying the natural environment. It will further prolong the harvest period, increase crop yield, quality improvement, and keep the availability of commodities frequently.
Protected cultivation enables cultivators to produce several folds of a good quality product which is difficult in normal conditions due to climatic and constraints. If the recommended and needful package of practices is adopted skillfully with exactness, any crop can be grown in any season, at any place using protected cultivation. It enables to control climate (temperature, humidity, wind, and light intensity, etc), atmospheric gas composition (mainly CO2 concentration), fertilization, watering, pest and diseases, etc which results in better plant growth, better reproduction, minimized harmful effects of different factors such as climate and agronomy and higher production with a better quality of produce.
Limitations of protected cultivation of vegetables and other produce
In case if you miss this: Organic Brinjal Farming.
- The high cost of initial infrastructure (capital cost).
- Non-availability of skilled human power and their replacement locally.
- Lack of technical knowledge of growing crops under protected structures.
- All the operations are intensive and require constant effort.
- Requires close supervision and monitoring.
- A few pests and soil-borne pathogens are difficult to manage.
- Repair and maintenance are major hurdles.
- Requires assured marketing, since the investment of resources such as time, effort, and finances, is expected to be very high.
Production practices of vegetables and other produce in protected cultivation
Selection of site – The selection of sites for taking up protected cultivation is a critical step and this has to be done with utmost care. Places having high rainfall and humidity are not suitable for Protected cultivation since this encourages many foliar diseases. Also, the areas with high wind velocity are not suitable because they are likely to damage the structure and the polyethylene sheet frequently, thereby enhancing the maintenance cost of the structure. Avoid the location or area where heavy rains accompanied by gusty winds are prevalent to avoid damage to the protected cultivation.
Greenhouse structures – The greenhouse structure is designed depending on the prevailing local climatic conditions. A good number of different types of structures are built for protected farming. Though, cost-effective poly house and net house structures are most commonly used to grow capsicum in our country.
Net house (Shade net house) – The growing of vegetables in the net house is the cost-effective method. It is due to the easy availability of the granite pillars, which can give good strength to the structure and highly durable. Net houses are constructed using granite stone pillars of about 12 feet height, 8 inch X 4-inch thickness. These pillars are located at 2 feet depth inside the soil with concrete cement grouting. The uneven and sharp edge of stone pillars on the top has to be covered with smooth materials such as rubber tubes to avoid tearing of net. A Galvanized (GI) wire grid is provided on the top of the granite pillar to support the shade net. Over the GI wire grid, 50% HDPE white shade net is fixed to support another layer of shade net (green or black with 35% shade), (High-density polyethylene) which is movable or retractable. This additional shade net is used during hot summer middays (Feb-June), sparingly during the winter season and whenever the sunlight is more between 11.00 am to 3.00 pm UV stabilized 40 mesh nylon net is carefully provided on all sides of the net house. Construction of net house costs about Rs.180-200 per square meter.
Polyhouse – This structure gives better protection compared to the net house due to total avoidance of rainwater entry into Polyhouse and then leaf diseases can be easily controlled. Yield is normally 15 to 20 percent more in Polyhouse compared to a net house. Galvanized pipes are used to construct a poly house and in some cases, farmers use wooden or stone pillars that require a less initial investment. Transparent UV stabilized polyethylene film; 200-micron thickness is about 4 used for covering the poly house roof. It is provided with retractable or movable shade nets, at 11 feet height just below the structures from ground level. The sides of the Polyhouse structure are covered with 200-micron thick polyethylene film to a height of 3 feet from the ground level. The remaining height of the sidewall is covered with a 40-micron white-colored insect-proof net from all the four sides. Construction of poly house costs about Rs.500 per square meter.
You may also check this: Plant Nursery Project Report for Bank Loan in India.
Net house and Polyhouse are provided with an antechamber with two doors constructed at opposite directions where entry or exit to the poly house or net-house. Care must be taken not to open both the doors simultaneously to avoid the entry of pests into the protected structures. A small concrete trough of about 2-meter length, 1-meter breadth, and 2-inch depth should be prepared between the two doors of antechamber for facilitating washing legs in the disinfectant solution (Potassium permanganate) to prevent any contamination inside the Polyhouse or net-house.
Crops are grown under protected cultivation
The major crops grown under protected cultivation include floriculture crops like rose, gerbera, carnation, anthurium, Lilium, orchids, and chrysanthemum, etc., and the vegetable crops such as tomato, yellow and red bell peppers (from the capsicum family), cucumber, leafy and exotic vegetables, etc.
A high value, short duration and small size vegetable crops are being most suitable crops under protected cultivation. In India, particularly in the hill the sweet pepper, tomato, and cucumber are being raised. However, leafy vegetables are suitable for protected cultivation. Cabbage, cauliflower, tomato, brinjal, capsicum, beans, pea, and coriander can be successfully grown under protected cultivation conditions at a high altitudinal region.
Production system for vegetables under protected cultivation
If you are interested in this: Custard Apple Cultivation Income, Yield, Project Report.
Geoponics or soil system
In this system, plants are grown in natural soil under protected cultivation. It has some demerits such as disease and insect incidence in soil. Flood irrigation water causes a high water table which reduces aeration, thereby plant root growth.
The soilless cultivation has increased significantly due to the use of methyl bromide as a soil disinfectant between crop cycles. New types of substrates are increasing in the same way to increase crop yield and quality for the plants grown in the soil. Several types of substrates are used as soilless media and it protects the crops from different soil infections such as coconut fiber, perlite, vermiculite, rock wool, peanut hulls, rice hulls, and coco peat, etc.
In hydroponic system plants are grown in nutrient and water solution without soil. Terrestrial can be grown with their roots in the mineral solution only or an intermedium, such as perlite or gravel.
Plants are grown in troughs, tubes, and other types of chambers, and roots are hung in air sprayed with nutrient mist. So, it easily absorbs nutrients and oxygen. This method has less chance of root diseases.
Temperature maintenance and water management in protected cultivation
The several crops can be grown in a wide range of temperature, but for better plant growth and development individual crops requires a specific range of temperature. It is mainly possible under protected cultivation.
Water is the most important factor that affects the production system of crops. It is not possible to grow the crop during the high rainfall, as vegetables are succulent and tender, high rainfall will drop the quality of crops. To reduce the consequences of high rainfall and high wind, protected cultivation is the most suitable technique. It will produce a high quality of plants throughout the year.
Emerging challenges for protected cultivation in India
The protected cultivation in India is facing a lot of constraints such as the loss of productive soils through urban intrusion, loss of low-cost labor, maintenance of temperature, humidity, light management, fertigation, irrigation system, lack of proper knowledge of harvesting, continuous electricity, and water supply, unavailability of market demand varieties, low risk-taking availability, lack of motivation, lack of suitable price policy and lack of created facilities. Then, these challenges affect the progress of protected cultivation in India.
In case if you are interested in this: Profit in Red Chilli Production.