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Ornamental pot plants should be potted in small pots according to the size of the plants. Any kind of pot/container which can hold medium and provide aeration is suitable. The most common container is the plastic or clay pots. Plastic pots should be preferred because it retains moisture longer than mud pots. Plants should not be disturbed frequently and re-potting done only when absolutely necessary.

Potting media

Different types of growing media may be used for ornamental pot plant cultivation, but it is crucial that it must retain a certain amount of moisture and be well draining. Different plants require different substrate in which they would thrive. Conditions of the plant experiences in nature should think before choosing the media. Tropical plants require more water naturally compare to subtropical and temperate ones. For irrigating with sprinkling can or hose, it is better to use materials that drain well and decompose slowly while for drip irrigation heavy potting material should be used. The most important thing is to match watering habits to the potting material. Growing conditions play a most significant role in deciding on a medium. If there is no problem in providing a constantly humid environment due to climate or if growing in a greenhouse, the moisture retention on thepart of media is less of a concern. Ambient temperatures play a role here, as well, as warmer temperatures tend to increase the evaporation of water and along with the drying rate of the medium. The personal tendencies and how much time might be spending to water plants is another significant factor in choosing a medium. The combination of potting materials that will work best for garden plants mainly on Plant structure and root structures:

Any substance or mixture of substances intended through physiological action, for accelerating or retarding the rate of growth or maturation, or otherwise altering the behaviour of plants or the produce thereof are known as plant growth regulators. It does not include plant nutrients, trace elements, nutritional chemicals, plant inoculants and soil amendments.

Plant hormones are organic compounds other than nutrients, synthesize by plants and regulate plant growth and development. They are active in very low concentrations, produced in certain parts of the plants and are usually transported to other parts where they elicit specific biochemical, physiological and morphological responses. They are also active in tissues where they are produced. The term plant growth regulator is usually used to denote a synthetic plant hormone, but most of the synthetic compounds with structures similar to those of the natural hormones have also been called hormones. For instance, the synthetic cytokinin, kinetin is considered a hormone.

Lawn

The lawn is a plot of closely mowed grasses. It is composed of thousands of individual plants crowded and forced into a very unnatural growth habit. It is an integral part of the garden. It is basically an area of land planted between gardens covered with grass and other low lying plants.

Lawn is one of the most important features of a garden. A well kept lawn makes a garden look extremely beautiful. It looks like a beautiful green carpet amidst colourful flowers in a garden. Lawn can be called as turf, pitch, field or green depending upon its plantation and usage. Selection of lawn grass depends upon it usage and its season of plantation. Though a well maintained lawn requires a little of patience and care, the final results are always very beautiful and soothing. Scientific reports say that lawns reduce energy consumption through it soothing effects and the green grass prevents soil erosion as well as cut down noise pollution in the urban areas.

Pruning is a regular part of plant maintenance involving the selective removal of specific plant parts. Although shoots and branches are the main targets for removal, roots, flower buds, fruits and seed pods may also be pruned. Pruning wounds plants, but plants respond differently to wounding than do animals. In plants, damaged areas are covered by callus tissue to close wounds. Another response to pruning occurs inside plants. Chemical boundaries form around wounded areas, walling off or compartmentalizing the wounds. Compartmentalization limits any decay that results from wounding, or from the natural death of branches. Use pruning techniques that minimize plant wounding and speed wound closure.

Weed is a plant that is growing in the wrong place. Weeds have many mechanisms and characteristics that enable them to compete, having thick waxy cuticle leaves that can be resistant to some chemicals, fast reproduction methods, the ability to reseed in 6 week cycles and deep tap roots enabling the weed to survive in compacted dry ground conditions.

There are many reasons to control weeds in annuals/biennial and perennial ornamentals. Weeds compete with the plants by absorbing essential nutrients and water, or by blocking light or air circulation. Weeds dramatic reduce the growth of the plants. The greatest damage is often done when the weeds and ornamental plants are small. Weeds also interfere with harvesting by physically hindering. They lower flower quality further by harbouring insects, such as whiteflies, thrips mites, slugs, snails and/or diseases.

Growing under optimal conditions for the flower will reduce the ability of weeds to compete against the crop. Controlling humidity/ventilation, water, light, pH, nutrients and temperature all figure prominently in providing flower optimal conditions. A plant health strategy to greenhouse weed control contains three principal elements, prevention/sanitation, evaluation of water quality and using all controls available physical, cultural and chemical. Prevention and sanitation can include the use of mulches in orchidhouse weed control. Rice hulls, perlite, pumice, corn gluten meal bark, Penn Mulch - pelletized recycled paper and human hair have all been used for this purpose. Prevention also includes, eliminating air borne weed seeds from entering the greenhouse by screening vents and other openings and preventing perennial weeds from growing under foundations. A 1-3 meter weed free zone should be maintained immediately adjacent to the greenhouse.

The term essential element was proposed by Arnon and Stout (1939).They concluded three criteria must be met for an element to be considered essential. These criteria are:

1.A plant must be unable to complete its life cycle in the absence of the mineral element.

2.The function of the element must not be replaceable by another mineral element.

3.The element must be directly involved in plant metabolism.

The number of elements considered essential for the growth of higher plants now varies from 16 to 20 or more, depending upon the definition of essentiality. Other scientists such as Nicholas (1961) believed that an element should be considered essential if its addition enhances plant growth even though it merely substitutes for one of the 16 elements that Arnon declares to be essential. For example, sodium can substitute in plant nutrition for some potassium and vanadium for some molybdenum, Nicholas would consider both sodium and vanadium as essential, but Arnon would not. On the basis of the criteria used, Arnon specifies 16 elements and Nicholas 20 elements as being essential for the growth of higher plants. Three other debated nutrients are nickel (urea transformations), cobalt (N₂ fixation) and silicon. These criteria are important guidelines for plant nutrition but exclude beneficial mineral elements. Beneficial elements are those that can compensate for toxic effects of other elements or may replace mineral nutrients in some other less specific function such as the maintenance of osmotic pressure. The omission of beneficial nutrients in commercial production could mean that plants are not being grown to their optimum genetic potential but are merely produced at a subsistence level.

Bulbs

Floriculturists use the term “bulbous” to include a wide array of perennial plants that grow from underground organs, including bulbs, corms, tubers and rhizomes. Any plant described as bulbous will normally have a swollen root or stem or even leaves underground (Some orchids and other plants have swollen stems – above ground). Bulbs, corms, tubers and rhizomes are perennial plants organ that are part of a plant type called bulbous plants in which part of the plant has evolved into a below-ground storage unit where food created one year is used to nourish the plant in the next. They are valuable in the garden for many reasons. Spring bulbs appear early, before most perennials have started to grow again after the winter. They can also add color to containers when other plants are not ready to face the danger of frost. In summer, bulbous plants such as Alliums and lilies can provide stately interest, while autumn crocuses and tiny hardy cyclamen can cheer up the garden toward the end of the season. The purpose of the bulbous part of the plant is to store food for the plant parts that live above ground to enable the plant to survive adverse conditions. The leaf bases may resemble scales, or they may overlap and surround the centre of the bulb. A modified stem forms the base of the bulb and plant growth occurs from this basal plate. Roots emerge from the underside of the base, new stems and leaves from the upper side. Most true bulbs have their scales closely packed together such as Hyacinthus but some types, such as the Lily (Lilium), they are loose and swollen. Most popular bulbs have a papery skin, the tunic, whose function is to protect the tissues within. Some true bulbs such as the Lily do not have a tunic and are therefore, easily damaged by rough handling. Cardio crinums dies after flowering but other bulbs are perennial. Vegetative reproduction in true bulbs is by means of offsets called bulblets.

Shrubs are usually woody or semi-woody perennial plants; their branches arise from the base of the plants and grow up to the height of 3 to 4 meter. Many shrubs, which are more or less prostrate, make excellence ground flower. Availability of a large number of species & cultivars, a wide range of variation in shape & size of the plants, diversified types of leaves, growth habit, remarkable ranges of size, shape, colour of flowers & the variety of fragrance have made the shrubs as important garden plants. Several species of shrubs have unusually attractive colours.

Most of the shrubs are hardy & grow in all types of soil with little attention. Although some plants flower almost throughout the year, in most cases they are seasonal. A selection can be made in such a way that some plants in the shrubbery will be in bloom in any season of the year. Most of these plants are fairly quick growing and when vegetatively propagated, start flowering in the first year. Plants like Bauhinia acuminata (Kanchnar), Cassia alata (Candle Bush), Vinca rosea,which are usually grown from seeds also produced flowers in the first year.Shrubs can be classified into three groups according to the requirement of the sunlight for growth & flowering:

Climbers can be used to break the bareness of long walls, soften posts, frame doors and windows and beautify window boxes. With a fence or trellis, they can be used for screens, making a background for flower garden or quickly turning an ordinary porch or patio into a private, shady living centre. Some slower growing climbers are useful as container plants for patios. On the down side, most vine species have the potential to become invasive, spreading to areas where they may not be desirable or becoming too large for the intended area.

Types

Climbers are characterized as three types based on how they cling to a support. The kind of support needed depends on whether the Climbers cling by twining stems, orby specialized structures such as tendrils, adhesive disks and aerial roots. Climbers with twining stems wind around a support as they grow (Fig. 5.2). Examples of plant with twining stem sinclude bitter sweet, wisteria and trumpet creeper.Tendrils resemble thread like stems that wrap around any structure they contact (Fig. 5.1). Examples of plants with tendrils include grape, pea, and cucumbers. Some Climbers have specialized structures for clinging to a support with a disk-like suction cup (Fig. 5.3). Examples include Boston ivy and Virginia creeper. Other Climbers cling by means of small, aerial roots that attach to rough surfaces such as mortar, wood, and tree trunks (Fig. 5.4). Examples include English ivy, trumpet creeper and winter creeper euonymus.

Annual flowers are a group of herbaceous plants which grow from seeds, produce flowers, set seeds and complete their life-cycle within one year or one season. They provide a beautiful display of colours in the garden. Whether it is a small home garden or a big public garden, it is incomplete without beds of annual flowers. They enhance the decorative value of a garden within a short span of time. At their blooming time, one feels elated when a rain of beauty drizzles in the garden.

Classification of Annuals

Based on season, the annual flowers are divided into 3 groups—winter season, summer season and rainy season.

Winter season annuals

This group includes a large number of seasonal flowers. The important ones are acroclinium, agrostemma, amaranthus, anchusa, annual carnation, annual chrysanthemum, antirrhinum, arctotis, bells-of-Ireland, brachycome, calceolaria, calendula, campanula, candytuft, celosia, China aster, cineraria, clarkia, cornflower, daisy, delphinium, dianthus, dimorphotheca, echium, eschscholzia, gazania, godetia, helichrysum, helipterum, hollyhock, gypsophila, limonium, linaria, linum, lupin, marigold, matricaria, mesembryanthemum, mignonette, mimulus, myosotis, nasturtium, nemesia, nicotiana, nemophila, nigella, pansy, petunia, phlox, pimpinella, poppy, rudbeckia, salvia, saponaria, scabiosa, schizanthus, senecio, stock, sweet alyssum, sweet pea, sweet sultan, sweet william, venidium, verbena, viola and wall flower.

Climate and Ornamental Crops

There are many factors which affect the production of the ornamental crops. It may be internal or external factors. Climate and soils are the chief natural factors on which the success or failure of ornamental crops production is dependent. A knowledge of the effect of various soil and climatic conditions on ornamental crops production is very essential for every prospective to grower, climate includes several factors like temperature, relative humidity, rainfall, wind, hail, light whereas, soil covers such factors as moisture supply texture, pH etc.

Temperature: The rate of development of a plant (the leaf unfolding rate) is a function of temperature. As temperatures increase, the leaf unfolding rate increases. If the temperature exceeds the maximum temperature, plants experience stress and leaf unfolding rate declines. Given the high costs of fuel, many growers are tempted to reduce the greenhouse temperature to save money on fuel. Because the rate of crop development is dependent on temperature, reducing temperatures increases production time of all crops. However, some crops will be more severely delayed than others. Reducing temperatures from 20°C to 16°C increased time to flower of Salvia farinacea by 13 days. This same temperature drop only increased days to flower of pansy by four days. For crops that are severely delayed by lower temperatures, reducing the growing temperature may actually increase total fuel costs for producing that crop. Every plant has fairly well defined range of temperature to which it is tolerant and below which the plants of that variety are liable to be injured to a more or less extent.

Classifications and Nomenclature

Plants can be classified according to the following criteria: (1) botanical, (2) descriptive and (3) agricultural. Botanical classification is based on the morphological characteristics of plants as well as on their anatomy, physiology and DNA sequences. Descriptive classification is based on the environmental adaptation, growth habit and other observable features. In agriculture, plants can be broadly classified as either useful or useless. Those which are useful are called crops while those which are not useful are called weeds.

A common, well-defined system of crop classification is important in crop science and agriculture. Grouping of plants following established systems will simplify plant collection initiatives, research and breeding specialized development efforts. Having standardized botanical names will also facilitate efficient communication, dissemination and retrieval of scientific information. Additionally, the grouping of crops will indicate that these crops may have similar uses, adaptation, growth habits and methods of culture. Classifying crops by family is likewise important in intergeneric grafting. To students of crop science, a list of crops under the various agricultural classifications will be a useful reference in crop names and identification and as a review guide. To the farm manager himself, the same list will offer innumerable benefits in finding alternative crops for specific uses.

Despite these advantages, however, classifications of crops in agriculture vary from place to place and from one country to another due to differences in the primary usage of certain crops, intensity of care, extent of cultivation and other criteria under consideration. It is not uncommon to find crops having two or more classifications, used simultaneously, alternatively or sequentially. FAO(2010) in its report entitled “Crops Statistics - Concepts, Definitions and Classifications”, expressed its difficulty in the collection and presentation of statistical data due to differences in the concepts, definitions, coverage and classifications” of crops which are grown in different countries.

Garden Rakes

1.For use with moving debris.

2.Aids in the cleaning process.

3.Proper use is with two hands.

Soil temperature plays an important role in plant growth. Solar radiation received on the earth surface raises the temperature of the soil surface from morning to solar noon followed by a decline until the next morning. Soil temperature gradients established on the surface lead to flow of heat downwards causing a rise in temperature of lower layers. These variations in temperature affect germination, emergence and further growth of plants. Several types of thermometers such as mercury or liquid in glass, bimetallic, bourdon gauge, thermocouples and electrical resistance have been used in soil research but the use of thermocouples and thermistors has been found most useful. A brief description of different types of thermometers used in measurement of soil temperature is given below:

Liquids in Glass Thermometer

A liquid-in-glass thermometer (Figure 20.1) consists of a capillary glass tube with a bulb at one end filled with a thermometric liquid (mercury), vacuumed and sealed. By reading the position of the liquid level on a scale the temperature value can be obtained.

The ratio of soil air-to-soil water permeability indicates the magnitude of breakdown of structure as a result of wetting. A value of one indicates no change in structure and a value greater than one reflects a deterioration of soil structure.

Principle

The permeability of soil to air can be obtained essentially in the same way as the permeability of soil to water. The measurement of permeability of soil to air involves the preparation and placement of the soil in a suitable container with provision for monitoring pressure differential across the sample and the rate of flow of air through it. For steady state case, this involves measurement of inlet and outlet pressures and the volume flux of air. The suitable form of the Darcy’s equation for calculating permeability of soil to air is:

Soil aeration signifies the ability of a soil to supply oxygen to actively growing roots and soil organisms. Because of constant biological activity causing oxygen consumption and carbon dioxide evolution, the oxygen present in a soil pore or oxygen renewal by mass flow becomes inadequate to meet the plant demand. A continuous diffusion of oxygen from atmosphere to soil and to plant roots through the wetted pores plays an important role. The oxygen reaching plant roots has to diffuse not only through the gaseous phase in the soil pore and wetted pore neck but also through a water film that is present on the hydrated root surface.Lemon and Erickson (1952) suggested a platinum microelectrode method that simulates the field situation. In this method measurement of the rate of oxygen diffusing through the liquid phase to a reducing surface similar to the plant root.

Infiltration rate refers to the volume of water entering into the soil per unit area in the unit time, when the soil is subjected to a shallow depth of ponding at the surface. Under continued ponding, the high infiltration rate in the beginning decreases to a constant value, known as final infiltration rate. The reduction in infiltration rate is due to combined effects of reduced hydraulic gradients, dispersion of aggregates, blocking of pores, cracks and channels, and swelling of colloids. Numerous techniques for measurement of infiltration rate have been developed to meet specific needs but use of double-ring infiltrometer has given consistent result in a variety of conditions.

Principle

In double-ring infiltrometer method, a small representative area in the field is bounded by two concentric metal rings (Figure 17.1) which permit impounding of water over the soil within the rings. The rate fall of surface of water ponded on the soil in the inner ring is taken as the rate of water intake or infiltration rate. In the cropped field, infiltration rate can be measured only within the rows and for which the diameter of the cylinders may be changed to meet the specific needs. The measurements under wetland conditions should be made from a distance of about 40-50 cm to avoid pressure effects.

Hydraulic conductivity is an important soil property that determines the ability of a soil to transmit water. A method of measuring hydraulic conductivity of saturated soil using undisturbed soil core is described in this exercise.

Principle

Flow of water across a soil layer or a sample of known dimension can be best described by Darcy’s law expressed as:

Water holding capacity of soil is the amount of water that a given soil can hold against the force of gravity. Soil texture and organic matter are the key components that determine the water holding capacity of a soil. Soils with smaller particle sizes (silt and clay) have larger surface area and can hold more water as compared to sand which has large particle sizes and smaller surface area. It is an important hydro-physical characteristic of a soil because it provides simple means of determining useful moisture levels to maintain soil for good plant growth. Detail procedure for determination of water holding capacity of soil using Keen box method (Piper, 1966) is described here.

Over most of the wetness range in which plant roots normally function, all the water in soil is controlled by matric forces. A relationship between water content and matric or soil water suction is referred to as water characteristics of the soil. Increase in matric suction is associated with decrease in water content in the soil and the process is known as desorption. On the other hand with decrease in suction soil moisture content increases and this process is known as sorption. The curves showing relationship during progressive intake and withdrawal of water are known as sorption and desorption curves respectively.

Tensiometer is suitable for finding out soil water characteristic at tension values below 2.0 kPa, whereas gas phase pressure is required for higher tensions. A pressure chamber containing a porous membrane or a ceramic plate with all its accessories to provide regulated compressed air is most convenient. A detailed methodology to determine water characteristic curve by pressure plate apparatus is described below.