Monday, June 25, 2012

The Orchid Family


The orchids are members of a distinct family known as Orchidaceae that has been derived from lily-like plants.
Orchidales are so much closely related to the Asperagales that sometimes it is merged with the latter. This order is characterised by the following shared primitive features: Zygomorphous, epigynous flowers, wet stigma, simultaneous microsporogenesis and endosperms arrested by an early stage or wholly inhibited.
Orchidales, as conceived by Dahlgren and Rasmussen, comprise three families, such as, Apostasiaceae, Cypripediaceae and Orchidaceae. In most published works, these families have been, however, united into one, that is Orchidaceae. Among these, the system of Dressler , revised by him in 1993, has been universally hailed as the most phylogenetic one for Orchidaceae. More recently, Szlachetko in his system of classification has tried to improve Dressler's system by avoiding cases of cladistic analysis that have often led to the formation of monothetic groups. For example, Dressler  has included two highly morphologically and anatomically different groups like Dendrobieae and Vandae under the Dendrobioid subclade basing only on the presence of stigmata or spherical cells. Szlachetko  justifies the maintenance of the three separate families, as above, based on the study of generative structure, which according to him, have developed differently. Apart from the difference in the gynostemium structure, the three families differ in the organization of the perianth as well.
Type: Orchis Linn.
Plants variable in habit; herb, vine or shrub-like, sympodials and monopodials; autotrophic or occasionally micotrophic i.e. saprophytic. Roots clustered or scattered along the stem or rhizome, with or without velamen. Storage organs of different forms. Leaves plicate, convolute, duplicate or terete, occasionally scale-like, cauline or basal, sessile or petiolate, articulated or not. Inflorescence terminal or axillary, forming a spike, raceme or panicle or capitate, single to many flowered. Flowers of various sizes and shapes, resupinate or not; the median tepal of the inner whorl transformed into a lip, usually different from the other tepals; lip sometimes similar in shape and size to the perianth. Ovary usually one-chambered, but occasionally three-chambered. Gynostemium often tied with the basal column, foot free or agglutinate with the ovary. Column part formed by the complete or partial fusion of the staminodes; filament and style usually well developed, but none in some groups; occasionally the style and stigma are borne at the end of the column. Stigma triple, double or single-lobed, often greatly modified, concave or convex, entire or split into three parts, wet. The median stigma lobed, modified into the rostellum, a structure of various shapes and sizes, producing a viscidium, usually single, but double in several genera, cellular, rarely semi-fluid. The viscidium sometimes produces a hook-like structure, the so-called hamulus. The tegula originates on the abaxial surface of the rostellum.

 The single anther, representing the median of the outer whorl, is fertile, erect, reflexed or incumbent, fixed or movable or detachable; connective thick, fleshy or wide, separating or covering both locules or two anthers representing the laterals of the inner whorl fertile; staminode shield-shaped or none or all the three anthers representing the inner whorl fertile . Pollinia usually compact or sectile, rarely granular, of monads or tetrads, often partially sterile forming caudicles of different shapes and structures; or pollen grains not forming pollinium, powdery or gathered in a sticky and paste-like mass. Staminodes, representing the lateral anthers of the inner whorl, rarely becoming free, finger or wing-like, usually connected in the column part, forming structures of various forms, sizes and functions. Fruit capsular, sometimes fleshy. Seeds tiny, adapted to anemochory, exceptionally to zoochory or hydrochory.

Sunday, June 24, 2012

Orchids Of The Lip


The lip is the most prominent member of the perianth. It is the highly specialized floral part of the flower and is extremely complex and variable. Sometimes it is broadly attached to the base of the column or over its entire length rigidly and therefore immobile. It may be attached to the tip of the columnfoot immovably or loosely hinged to it and is exceedingly mobile.
It may be sessil or short or long-clawed . The lip may be membranous and antrose i.e. directed upward and forwar or thickly fleshy and strongly reflexed; or may be recurved only at the tip. Very often it is porrect. The basal, middle and distal portions of a lip are often distinguishable and termed as hypochile, mesochile and epichile respectively. The hypochile is occasionally laterally stetched backwards as a lobe known as auricle.
The lip may sometimes be undivided and then usually concave, ventricose, cymbiform  porrect. Occasionally as in Androcorys pugioniformis, the unlobed narrowly oblong-triangular lip with a broad base is excavated into two deep oval, parallel pits. More often it is divided into three or more lobes or segments, commonly at the base. Very often the lip is divided at the middle or at the apex. The outer lobes are known as the lateral lobes or sidelobes. The lobes may themselves be entire, lobed or deeply divided. The lobes or the segments of the lip may be broad. The lateral lobes may be erect or spreading. It may be entire (Pachystoma) or of fimbriate to filiform segments .
Sometimes the lateral lobes of the lip or the entire are convolute, embracing the column and giving the lip a trumpet shape. Often the lateral lobes are short and indistinct. The midlobe may be large and spreading  or small and tongue-like (Pecteilis). It is generally entire or sometimes divided into two The edges of the midlobe are often wavy, recurved or crisped Sometimes the lip is deeply bifid or two-lobed at the apex as in Listera pinetorum, Neottia listeroides etc. But at times it is bibbed along the length as in Cephalanthera damasonium. The space between the lateral lobes is termed as disc.
The inner face of the lip, especially at the basal region or on the disc, is provided with decorations of various kinds that are intended to serve as guide-markings on the landing platform  for the pollinators. These surface features are growths usually in the shape of longitudinal crests , keels , lamellae or may be of various kinds of thickenings or rows of papillar warts . The form of the callosities may be simple but may be occasionally complex. In several species like Eulophia graminea, Pleione hookeriana the outgrowths are in the shape of fat hairs along the veins. Occasionally there are movable hairs, which catch slightest movement of the wind.
The lip at the base may have two lateral tubercles or knobs without other decorations on the lamina. The upper surface of the lip becomes papillose, as in many species under Bulbophyllum, Cirrhopetalum, etc. Sometimes as in Monomeria longipes, the lip is very puberulose, the distal half densely and shortly stiff hairy. Often the lip is provided with coloured markings, blotches or stripes.
The lip may be variously shaped like a boat , a funnel , a slipper or shoe. The base of the lip is often variously saccate or has a sac-like to tubular extension — a hollow appendage, called the spur. It usually bears glandular tissues inside and secretes sectar dear to the insects.
The spur is variously shaped like globose , conical , clavat, straight or bent to strongly curved forwards . It is shallow as in Chiloschista, Geodorum, and Thrixspermum; deep, basin or jug-shaped as in Gastrochilus and Pomatocalpa etc.; long tube-like as in many Calanthe, Habenaria etc. Sometimes it is short and hidden by the lateral sepals or conspicuously long upto and In a few cases like the terrestrial Corybas, Satyrium or the epiphytic Diplocentrum the lip has two collateral spurs.
The spur is often provided inside with calli at the bottom; papillae and glands, stalked or not ; hairs warts or with various other projections on its back or front walls Cleisostoma, Pomatocalpa, Staurochilus. Rarely it is septate or has a fleshy transverse growth at the mouth of the opening. These thickenings or projections on the inner side of the spur furnish important characteristics for identification. In Cottonia peduncularis, an epiphytic vandaceous orchid from peninsular India, and extending to Sri Lanka, the lip in its structure, colour and texture remarkably resemble a certain bumble-bee. This is a typical case of mimicry — a feature not uncommon with orchids.

Orchids Of Subtropical Zone


Mixed forests bearing tall and medium sized trees with thick canopy of leaves characterize this zone. The moss covered tree trunks and branches, as also rock surfaces nearing watercourses, form ideal habitats for orchids. Heavy summer precipitation as also precipitation in the form of dew during night and early morning is the character of this region. During summer the day temperature may remain  that drops down to about at night. Winter here is cool and dry; the day temperature ranges between  with a cooler night. Relative humidity during the rainy season remains  Some of the best-known ornamental epiphytic orchids are found in this zone. This zone can broadly be divided into the following habitats.
Forest Vegetation
The mixed forests and secondary scrub vegetation forms major area under this region. Most of the popular epiphytic orchids with large and handsome flowers favour this vegetation. These are Coelogyne, Cymbidium, Dendrobium, Thunia (all sympodials); Arachnite, Renanthera, Vanda (all monopodials); the famous blue vanda (Vanda coerulea) and the red vanda (Renanthera imschootiana) come here. The other epiphytic genera are Bulbophyllum, Eria, Liparis, Oberonia (sympodial); Cleisostoma, Phalaenopsis (rnonopodial). There are many terrestrial genera like Calanthe, Crepidium, Liparis, Malaxis, Phaius that prefer damp forest floors, inhabit here.
Ca!carious rocks
There are some terrestrial genera like Paphiopedilum whose distributions are determined by the mineral contents of the substrate. Limestone or dolomite rocks when located on banks of perennial rivers or waterfalls under thick vegetation with high rainfall provide ideal habitat for the popular lady- slipper orchids. Paphiopedilum fairrieanum, F hirsutissimum, P. insigne, P. spicerianum etc. grow on the percipes and crevices of rock cliffs or rock faces on riverbanks.
Clay banks
Several terrestrial orchids like Anthogonium gracile, Crepidium acuminatum as also several habenaria allied genera like Habenaria, Pecteilis and Peristylus usually prefer clay banks located inside vegetation.
Bamboo and Palm thickets
The bamboo and palm thickets are a different type of vegetation and provide shelter to many popular terrestrial orchids such as Calanthe, Phaius, and the well-known lady slipper orchid Paphiopedilum venustum. Other terrestrial orchids growing here are several species under Eulophia and Nervilia.
Humus-rich Forest floors
On the forest floors are accumulated fallen leaves, twigs, and other vegetative debries. On decaying these make the top soil humus-rich, porus and light. Soil of such kind near the banks of perennial watercourses under shade remains moist and forms ideal habitat for many terrestrial orchids of evergreen in nature. Important among these are the jewel orchids, which comprise species from genera like Anoectochilus, Goodyera and Zeuxine. The substrate is also much suitable for the saprophytic orchids that are known to thrive on decayed vegetation. Several saprophytic species under the genera Cymb, Epipogium, Erythorchis, Eulophia , Galeola, Gastrodia occur here. Several species under the terrestrial genera Calanthe, Cheirostylis, Crepidium, Eulophia, Phaius also favour such habitats.

Saturday, June 23, 2012

Introduction Of Orchid


Orchids are renowned for their exquisitely beautiful and colorful flowers for which they are favourites of the flower lovers. Biologically complex plants as they are, they have equally drawn the attention of the botanists. The structure of the orchid plant as also the flower is very interesting. These are herbaceous plants with different growth habits. Some are terrestrial, i.e. grow on soil preparing their own food; some others derive their nutrient requirement directly from decaying material in the substrate and are saprophytes. But the majorities of them adopt a superterranean or aerial mode of living over trunks or branches of other plants, and thus, are known as epiphytes. They however prepare their own food and are never dependent on the host.
Orchids are very widely distributed over the globe except in the extreme hot or cold regions. To accommodate to the widely varying range of environmental factors, in a very large geographical area, the vegetative habits in the terrestrial forms have undergone enormous changes. The aerial existence of the epiphytic forms, although distributed in a comparatively smaller area than the terrestrials, too, necessitated highly varying modification in their vegetative forms. The plant structure in orchids is thus remarkably diverse and few other plant families match their vegetative diversity.
Orchids are a strange group of plants standing apart from the rest of the plant families. This is how they are. An orchid fruit contains inside it innumerable dust-like non-endospermic seeds. The peculiar mode of germination of these seeds require the association usually with mycorrhizal fungi. The presence of air space in the seed makes it lighter and buoyant to be dispersed over a wide geographical area. Orchid roots are covered with spongy dead cells called velamen, which protects the inner conductive channel, absorbs moisture from the air and clings to the host tree securing a strong position for the plant.
Flowers of orchids are found in incredible ranges of size, shape, colour and ornamentation. But it is the mode of construction of the flower and its efficiency in successfully carrying out the intended functions through the various floral organs that render orchids the wondrous creation of nature. The orchid flower has evolved many complexities for perfecting cross- pollination. This is easily noticeable in its flower structure. For example, the otherwise inconspicuous sepals have become colored like petals and one of the three petals, known as the lip, is variously shaped and decorated. By an extreme torsion or twisting of the pedicellate ovary through an angle of  flowering, the lip occupies a frontal position so as to serve as a landing platform for the visiting pollinator.
The pollen grains are agglutinated into neat little packets known as pollinia. The pollinia aim at fertilizing a very large number of ovules while avoiding unnecessary wastage of the pollens. The pollinia is provided with accessories by which it gets attached to the body of the pollinator. It is kept inside a pouch on top of a stump-like structure known as the column, in such an easily accessible position that, the foraging insect while probing the flower, would not fail to dislocate the pollinia and carry it way. The column has evolved through the fusion of the style and the filament The stigma, the female receptive organ, is suitably crafted, usually, on face of the column. The column is a unique and characteristic structure of the orchid flower.
An interesting feature of the orchid flower is the striking resemblance of many of them to various animal forms like bee, wasp, butterfly, moth, scorpion, frog, dove, tiger or even man (man orchid). Sometimes they adopt odd posture and attain popular names such as laughing orchid, soldier orchid, flying duck orchid and ghost orchid.
The diversity in their structure, the aerial existence and capability of survival in varying climatic condition show their adaptive excellence. This explains why Orchidaceae, largest among the flowering families with around successful and advanced in the plant kingdom. As an advanced family, orchids have tolerated wide crosses to allow free gene flow across specific limits, within and between the genera, to enable them move faster by strides in the path of evolution. Production of new species by hybridization is the speediest form of their evolution. Natural hybrids among orchids have been reported from early days of orchid collection. But it is the stupendously large number of man-made hybrids that have surpassed the scale of imagination. The artificial hybrids have flowers more beautiful than anything found in the nature. This aspect has been taken advantage of in the horticultural pursuit for better quality of flowers. Orchid cut-flowers, with better keeping quality (flowers remain fresh for months), now a days abundantly available, has become a very successful and alluring trade in the global market of floriculture.

Orchid Intra-familial Evolution


Orchidaceae as seen today has developed from a primitive stock and traversed through several lines of evolution at various stages of geological and geographical changes. Unlike in many plant families orchids do not have a fossil record. However several features in the living plants themselves, less complicated as they, are indicate the evolutionary track in this highly advanced group of plants.
The present day orchids are almost all monandrous i.e. with a single fertile anther. These have been derived from their counterpart with two or three fertile anthers, which are considered to be primitive. The evolutionary trend from the former form to the latter form can be seen in the vegetative form, floral structure (like the formation and the characters of the reproductive organs in the pollinia), the seed structure etc.
The orchids started living as terrestrials. In due course of time probably competetion for food in the land prompted some of them to migrate to the nearby bare tree trunks and branches for a spacious accommodation. The epiphytes were thus born at a later stage. These gradually perfected their modification in the several organs, mostly in the stem and the leaf, for better living.

Like in the general monocots, in the primitive orchids the leaves were mainly arranged spirally along the stem. The leaves gradually got reduced in numbers and they were arranged distichously and became articulate. Storage tissues were developed in the groups where it was necessary to store food, by making the leaves thick and leathery. The stem also developed special tissues for storage of food and became fleshy. In the terrestrials corms, tuberoids and rootstocks were the result of modification of the stems. In course of time the primitive multi-noded corms (Acanthephippium, Calanthe) gave rise to a form with a single node (Didicea, Tainia). In the epiphytic the sympodial form with uniformly thickened multinoded stem in Dendrobium, Eria and Thunia etc., gave rise to stems with a single node as in Bulbophyllum, Pholidota, etc.
The sympodial growth form of the stem with a limited or defmite annual growth and with formation of new lateral stem every year gave rise to the monopodial form of stem with unlimited or indefinite growth and a single growing point. Vanilla is the only terrestrial genus that is an extensive creeper with monopodial growth form. The usual terminal inflorescence was transformed to the lateral form. In the advanced monopodial form, lateral inflorescence became the rule.

In the orchid flower organization of the anther has played a very crucial role. In the immediate predecesser of Orchidaceae the six anthers were arranged in two alternating whorls of three each. The primitive orchids were basically of two types: (i) where the anthers of the outer whorl were suppressed - the triandrae and (ii) where the anthers in the inner whorl were suppressed — the diandrae in the lady's slipper orchids. With advancement there was further reduction of the anther and the monandrous form with only one fertile anther in the outer whorl came into being. Barring a few genera like Apostasia, Cypripedium and Paphiopedilum, all other genera found in India are monandrae.

The pollen grains in orchids, as has been said earlier, are united to definite masses called pollinia. The unicellular pollen grains have been variously united to give rise to simple, soft, mealy or granular pollinia, to sectile pollinia; or waxy to hard pollinia, naked or with various pollinial appendages, in the most advanced form. These characters are used in classification of Orchidaceae.
In the primitive form the single-celled pollen grains are free and contained in the four-locular anther in Apostasia (monads) or held by a viscous fluid as in Paphiopedilum and Cypripedium. In most cases the pollen grains are bundled into small units called tetrads. These tetrads in the primitive form are held by elastic threads and remain in a mealy or granular form under Spiranthoideae . Sometimes they are organized into granular packets known as sectile pollinia. Bases of these packets are prolonged into short or long tails that are pollinial in origin. Sectile pollinia are met in Spiranthoideae and Orchidoideae.

From a soft consistency in the primitive forms, the pollen tetrads tend to become gradually hard. In the less advanced form the tetrads are collected to firm masses called waxy pollinia. There are usually eight clavate pollen masses divided completely halfway between top and bottom, four masses in each cell, two smaller than the other two. This is met in Epidendroideae under the terrestrial genera Acanthephippium, Calanthe, Phaius etc. The pollinia is prolonged at base and held by a viscous or a pad-like mass formed from part of the rostellum. In the epiphytic form these waxy pollinia remain naked without prolongation or any appendages as in Eria (eight pollinia) or Bulbophyllum, Dendrobium, Oberonia .

In the process of advancement there was a tendency for further reduction of the number of pollen masses in the pollinium while getting harder. This is the case with Vandoideae. In the first case the pollinia got reduced to four laterally compressed discoid masses by the loss of four terminal masses. The pollinia here may be provided with appendages like caudicle, stipe or viscidium. The pollen masses were further reduced to hard or bony masses. They were usually notched, porate, foveolate or variously cleft; occasionally they were entire i.e. solid masses. These masses were provided with a well- developed appendage — the pollen kit consisting of caudicle, stipe and viscidium.

The epiphytic form in orchids is of later development. In this the monopodial growth form is of recent origin. Common ancestral form among the monopodial is a plant with strap-shaped or channelled thick leaves with usually large flowers. The lip here is without much ornamentation and the pollen apparatus is simple as seen in Vanda. From this form are evolved the advanced genera with reduction in size of the plant, leaf and of the flower. The lip developed complex outgrowths or callosities of various types; the pollen apparatus became more complex and specialized, the notched pollinia giving way to solid ones. With the complexity in floral organs, the flower has a tendency to become ephemeral. Chiloschista, Taeniophyllum etc. are a few genera where such reduction in the size of the plant, leaves and flower is observed. The plants have become aphyllous, the roots taking the functions of the leaves.

Friday, June 22, 2012

Generic Description Acampe Lindlley


An Old World genus of coarse monopodial epiphytes forming massive clumps, with fleshy strap-shaped leaves, a lateral raceme or panicle of peculiarly fleshy and brittle small flowers, marked by brown transverse bands. Lip adnate to footless column, saccate or spurred; sidelobes minute; midlobe ovate, fleshy, scabellus inside; sac without back wall callus, but usually hairy and often with a longitudinal median callus. Column short, with two terminal horns. Pollinia four in two unequal pairs; stipes strap-shaped to clavate, hardly twice as long as the diameter of pollinia; viscidium small, elliptic.
Acanthephippium Blume
An Indo-Malesian genus of terrestrial plants, with closely approximate, large, conical, multinodal pseudobulbs and a few plaited, articulated leaves. Inflorescence lateral on the young pseudobulbs, short, erect, few-flowered. Sepals cohering into an obliquely jug-shaped body, free at top; laterals much broader than the dorsal, decurrent on the columnfoot forming a mentum with it. Lip on top of columnfoot, very mobile, small, saddle-shape; disc with varying number of longitudinal keels. Columnfoot very long, up curved, distally free from sepals. Anther two-loculed; pollinia eight, waxy, in two separate bundles of four each, all cohering by a short granular stalk.
Acriopsis Reinwardt ex Blume
An Indo-Malesian epiphytic genus of sympodial plants with creeping, branched rhizome, clustered ovoid pseudobulbs covered at base by slender, silvery sheaths. Leaves apical, one-three, linear-lanceolate, petiolate. Inflorescence from base of the pseudobulb, erect, slender, simple or branched, with many well spaced, small, spreading, twisted flowers. Lateral sepals merged completely into a synsepal. Lip spreading, more or less three-lobed; bases of side lobes connate with the column above its middle forming a nectary; disc with short, erect lamellae on the mesial line. Column straight to S-shaped, with two styliform, horizontal or decurved processes on each side of the stigma, and cucullate concealing the anther; rostellum suberect, beaklike, bifurcate. Anther membranous, two-chambered; pollinia four, connate in two pairs, slender, on long, thin stipes; viscidium minute.
Acrochaene Lindely
A monotypic epiphytic genus from India and Thailand with closely approximate uninodal pseudobulbs and single, linear-oblong, coriaceous petiolar leaf. Inflorescence from base of the pseudobulb, pendulous; raceme long, laxly many-flowered. Flowers medium-sized, dull green, spotted-striate. Sepals spreading, the lateral pair obliquely adnate to the columnfoot to form a short mentum; petals shorter than the sepals, ciliate-fimbriate. Lip with a short claw, incumbent on and articulated to the end of the columnfoot, three- lobed; the basal lobes erect and broadly toothed at the apex; the apical lobe tongue-shaped and deflexed. Column short, thick, with blunt obscure arms; columnfoot long and straight. Anther broad, two-chambered; pollinia two, subglobose, cleft, attached below to a stout caudicle and a gland-like body at the base.
Aenhenrya Gopalan
A monospecific terrestrial genus endemic to South India belonging to the popular jewel-orchids; with decumbent rhizome, an erect beaded and mottled leafy stem and a terminal inflorescence with a single or rarely two large flowers. Lip large, three-lobed; hypochile rectangular, having a few fat hairs laterally at base; epichile elongate, tube-like; side lobes of lip clasp the stigma lobes; petals and rostellum form an upper canal. Column incurved, long, containing the tapering rostellar projection (sterile median stigma lobe); fertile part of stigma three-lobed; the lateral lobes at base of the column, triangular; a third narrowly triangular lobe on a horn like projection. Pollinia two, bipartite, with very long stipes (among the longest stipes known in the family), ending in an ovoid viscidium.

Aerides Loureiro
An Indo-Malesian genus, predominantly epiphytic, rarely lithophytic with branching long, stout stems, loriform leaves and a simple or branched, erect or pendulous raceme of large showy flowers. Sepals and petals subsimilar; lateral sepals ± decurrent on columnfoot. Lip stiffly hinged to end of the columnfoot, three-lobed; lateral lobes decurrent on the column, small or large; midlobe usually larger than the sidelobes or smaller and included between them, spurred; spur usually bent forward, with swellings or calli within. Column short, with a large foot. Anther two-loculed, beaked; pollinia two, cleft, on a narrow stipe; viscidium various.

Thursday, June 21, 2012

A Guide About Helianthemum Flower


Helianthemum is a genus of modest little evergreen shrubs or semi- shrubs which, in an unassuming way, are attractive at all seasons. When in bloom, however, they are among the most floriferous, vividly coloured, and spectacular of all dwarf shrubs. The elegant and graceful little flowers are often compared to cistus, or even to miniature single roses. Their relatively late and prolonged flowering season makes them particularly valuable for the rock- garden, as they are at their maximum beauty when all the earlier flowering plants such as alyssums, aubretias, iberis, etc., have finished. They are also ideal for planting in dry walls, on terraces, or alongside stone steps.
Helianthemums are native to the Mediterranean regions, Asia Minor, North America, and Europe as far north as Sweden. The name derives from the Greek helios and anthos , with allusion to the yellow blooms. Although profusely and continuously produced, the flowers last only one day, from sunrise to sunset. The plants are also real sun-lovers, preferring a rather dry, poor, even arid sandy soil which is slightly alkaline , in a very well-drained position. Among the one hundred or so species can be found specimens that thrive in the semi-desert areas of Asia and North America; while in Europe they are found growing in the mountains up to an altitude.They are small evergreen shrubs of dwarf semi-prostrate wide-spreading habit. Planted in dry walls or on steeply sloping ground among rocks, the plants assume a trailing, almost prostrate habit. They do not require any special cultural treatment but are not hardy. It is advisable to cut the plants back severely—reducing the size by about a half—after flowering in late summer The helianthemums grown in gardens are mostly of hybrid origin, with a wide range of colours and with single or double flowers.
Propagation can be effected from seed sown in flats or pots in cold- frames or unheated greenhouses in spring, or by means of cuttings of half-ripened growths in July, which should be placed in sandy soil in frames.
Helianthemum Chamaecistus Mill.
Native to Europe, particularly Sicily, Corsica, and other Mediterranean regions. A small shrub with little linear-oblong opposite leaves with recurved margins. Elegant little five-petalled single flowers; generally yellow, but variable in colour and sometimes pink or white. Although its maximum height is only about  fully developed plants often have a diameter of up to with a close compact habit.
Helianthemum glaucum Pers.
Native to Southern Europe. Distinguished from other species by its silver-white foliage which contrasts well with the small yellow single flowers. The leaves are also thicker in texture, downy on the undersurface, and hairy on the upper surface. It is these three species (H. apenninum, H. Chamaecistus, and H. glaucum) that have been instrumental in creating the vast number of garden hybrids now available.
Helianthemum Tuberaria L.
Native to Southern Europe. A dwarf semi-shrub almost with the habit of a herbaceous perennial. Leaves oval,, finely dentated, covered with white hairs on the undersurface. Flowers in diameter, yellow, single, and borne in loose terminal groups. Petals slightly dentated at the tips.
Helianthemum Hybrids
These are the Rock Roses most frequently grown in gardens. There is a wide selection of silver- and green-leaved forms and varieties, with single or double flowers ranging in colour from orange, yellow, or white to pink, red, or scarlet. Specialist nurseries catalogue at least thirty named varieties, all of which must, of course, be propagated by vegetative means from cuttings.


Wednesday, June 20, 2012

A Guide Flower For Garden


 But when grown for cutting they should be grown in a bed apart from the garden proper, and planted in rows to facilitate the essential staking and tying; thus, the unprepossessing aspect of the plant after flowering is not seen. Even indoors, the cut flowers require judicious placing and arranging; they need a very large vase and are best suited for use in large rooms, standing alone on a table, so that they can be seen from all sides. Exceptions to this are the smaller species, and the dwarfer G. colvillii, butterfly, and miniature hybrids, all of which are real gems in the garden. In a garden where there is an area of rough grass, the wild European species gladioli will give beautiful effects when planted in the grass—of particular interest for this are Gladiolus segetum and Gladiolus communis. Other European species such as G. palustris and G. byzantinus are also ideal for naturalizing, and under such conditions their often hard, rigid, vertical lines are minimized. They are hardy in localities where the ground does not freeze solid to the depth of the bulbs for periods of  weeks. In colder zones, they should be lifted in the autumn.

The genus is a fairly large one and comprises about species, with a wide distribution that includes Central Europe, the Mediterranean region, Central Africa, and South Africa—the area around the Cape of Good Hope, in particular, has about one hundred species, but not all of these are hardy. In gardens, however, the majority of gladioli cultivated at the present time are of hybrid origin.

The name gladiolus was originally coined by Pliny the Elder. It derives from the Latin word gladius (sword), because of the swordlike shape of the leaves. The genus was named by Tournefort, and gladioli were introduced into European gardens at an early stage, although the first to be cultivated for decorative purposes were the wild species, which remained the only garden gladioli until about three hundred years ago. In 1629 Gladiolus byzantinus was introduced into Europe from Turkey, while about the middle of the eighteenth century the first South African species were introduced. Hybridization started in France about 1841, when Bedinghaus, gardener to the Duc d'Aremberg, is believed to have crossed Gladiolus psittacinus with Gladiolus cardinalis, producing Gladiolus x gandavensis . Gladiolus x colvillii was raised in 1823 by Colville at Chelsea in England, by crossing Gladiolus tristis with Gladiolus cardinalis. Gladiolus x gandavensis was further crossed by Lemoine of Nancy in France, who produced Gladiolus x lemoinei in 1880. The one species that has played a major part in the evolution of the modern gladioli is Gladiolus prirnulinus. Introduced in 1887, it enriched the colour range to include shades of yellow, orange, salmon, and apricot.

Then, at the turn of the century, the normal shape of the flowers was varied by Pfitzer, who created varieties with fringed and ruffred petals. This transformation was further developed in the United States, eventually producing such popular varieties as Ruffled Champion, Sweet Seventeen, and Picardy. About 1900, Gladiolus x nanus was created; this was a hybrid that was earlier flowering as well as dwarfer than any other. These smaller forms soon found great favour for their gracefulness and for their greater resistance to wind and bad weather. In more recent times, both European and American growers have concentrated on obtaining hybrids with smaller flowers. In 1951 the Dutch firm Konyenberg en Mark introduced the butterfly or mignon type, with small flowers .In the language of flowers, the gladiolus, represents pain and tears, because "the flower bears the woeful cries of Apollo after he had unfortunately caused the death of his beloved friend Hyacinthus." In ancient times, young men wore garlands of gladioli at the nuptials of a companion, as an expression of sorrow at losing the affection of a dear friend.
Finally, a word concerning the perfume of gladioli. Hybrids which have originated from such species as G. tristis, G. carinatus, G. grandis, and G. caryophyllaceus have a fragrance similar to carnations, plums, honey, or freesias, or a mixture of all these. Some hybrids which can be especially recommended for their scent are:
Cultivation. In the flower industry, gladioli have attained great economic importance, and the past ten years have witnessed particularly rapid progress. In Germany, the most important growing centres are found in the lower Rhine districts and in Schleswig-Holstein, where between  are cultivated. In Holland as many as acres are devoted to commercial gladiolus growing, and large crops are also raised in California; while France, Italy, Spain, Morocco, Egypt, and Israel all produce gladiolus flowers for the market on a minor scale. The cultivation of gladioli native to Europe and the Mediterranean zones is not difficult from southwards. They thrive in any normal fertile soil, and when planted permanently the only precaution to observe is to allow the foliage to dry and die back naturally, removing the flower stem after flowering has finished so as not to weaken the corm through the production of unwanted seed. The species G. segetum, G. communis, and G. palustris are hardy where the winter temperature does not fall below about  for lengthy periods or where the ground does not become deeply frozen. However, Gladiolus illyricus can be left permanently in the ground where there is only light winter frost; while the South African species should only be permanently planted in practically frost-free areas (with the exception of Gladiolus tristis which will tolerate as much frost as the European species). Gladiolus corms propagate rapidly and multiply naturally, and if the corms are removed from the soil when dormant they can easily be divided.

The cultivation of the modern hybrids is somewhat different. The bulbs are normally planted from January to July, according to local climatic conditions, which means, in effect, that the first planting can be made in early spring when all risk of frost has passed. In many northern areas this first planting may have to be delayed as late as the first weeks in May. The commercially available varieties are classified as Early and Late, and the Early types should be planted first. The correct planting depth is according to the size of the corm; the distance between the bulbs . Neutral soil or slightly alkaline  soils are most suitable. The site should be well dug and enriched with composted manure; the soil must be well drained and in a sunny position. If the soil is too heavy, drainage can be improved by adding a quantity of coarse sand, although an excessively porous and very dry soil is harmful because gladioli like plenty of moisture.

 A period days is required from planting to flowering and if a quantity of bulbs are planted at intervals days, from the date of the first planting until July, a succession of bloom can be assured until October- November Immediately after planting, it is advisable to mulch the soil surface lightly with a layer of peat or well-composted leafsoil or manure to prevent the soil forming a hard crust and to conserve moisture. Gladioli require the most attention during June-August. Some experts advise the following fertilizing programme: immediately after planting, apply 6 tablespoon of one of the commercial brands of "complete" fertilizer to every square yard and scratch it in lightly; three weeks later, when growth has started, apply tablespoons  of ammonium sulphate per square yard; then, after another three weeks, apply tablespoons  of ammonium nitrate per square yard, or 1teaspoon of urea. Other growers prefer to use only organic fertilizers such as bone meal, dried blood, fish meal, etc. 

During this period  which in most districts is likely to be hot and dry, gladioli require an abundance of water, not only at the roots, but also for the leaves. If the leaves are sprayed regularly there is much less risk of the plants being attacked by such pernicious pests as red spider and thrips, insects to which gladioli are particularly susceptible when grown in a hot, dry climate. While the weather remains dry, a moderate supply of water should continue to be given until the foliage turns yellow, prior to dying down (which marks the beginning of the corms' dormant period). If the inflorescence has not been taken for use as cut bloom, it should be removed when all the individual flowers have withered and before seed formation begins. The foliage should not be cut back while it is still green, and when cutting the flower spikes at least a few leaves should always be left on the plant.

Corms can be lifted from the soil in October—November, when all growth has ceased. They should be dried outdoors in a shady position at a temperature of about  or, if more convenient, in a well- ventilated location such as a garage. Once again, do not cut off the leaves until they are completely dry. When dry the corms can be cleaned, inspected for disease or damage, and dusted with dieldrin or naphthalene (moth flakes) at the rate corms. The corms can then be placed in shallow wooden trays or boxes and stored in a dry, dark, well-ventilated place at a temperature. until the following spring.

Corms are offered for sale in various sizes, and the best size is about  in diameter. Gladioli are propagated from seed only when new varieties are being raised. The best sowing time is March, in a slightly heated greenhouse or in frames, pricking out the seedlings into nursery beds, and then allowing them to grow on to form corms. In autumn, the young corms should be lifted and dried in the same manner as those of the flowering specimens. Another method of propagation is to use the numerous little bulbils or bulblets that form around the older corms. These are about the size of a pea, and if the largest are selected in autumn, when the corms are removed from the soil, they can be kept during the winter with the dormant corms. In spring these bulblets can be planted apart in nursery beds, and grown on to form new corms.



The Edgeworthia papyifera Flower


The strange name of this genus might suggest some rare and almost unknown plant, but one species is widely cultivated in European gardens and in many parts of the United States, although few people are familiar with its correct name. It is so common in certain regions that it is frequently the only important shrub in even the most humble garden. The reasons for this widespread popularity of what might have so easily been a rare plant are its ease of cultivation, the ease with which it can be propagated its early-flowering habit, even before forsythias, and its deliciously fragrant flowers.
Edgeworthia papyrifera Sieb. & Zucc.
This is native to China and Japan and was introduced into Europe. It is one of the earliest-blooming shrubs in spring; in mild localities it blooms at the first sign of winter's end. At one time in China and Japan it was widely cultivated for use in making fine paper, such as that used for paper currency. The plant's branches are so pliable that they appear to be made of rubber. It is impossible to break them by bending and they are flexible enough to be tied into knots. This attractive deciduous shrub has a close, compact habit with a great many stems rising directly from its base. The leaves are mostly terminal, alternate, narrowly oval, entire, up to long, and dark opaque green. The inflorescences appear before the leaves and are terminal clusters up to, wide composed of small individual tubular flowers; intense yellow internally, creamy yellow externally, with a relatively wide mouth. The flowers are covered externally with fine silky white hairs and they have a strong, delicious scent. 

The inflorescence much resembles that of daphne, to which edgeworthias are closely related. Mature, well-developed specimens often have a diameter in excess of their height and are seen to best *effect when cultivated as isolated individual specimens so that their naturally rounded, very pleasing form can be appreciated. The plant can also be used to form an informal hedge, but it should not be pruned or otherwise restricted. Cultivation is very easy; the plants will thrive in any ordinary garden soil, either acid or alkaline as long as it is well-drained. They like full sun, but will also tolerate partial shade. Propagation can be effected by means of the basal growths that can easily be detached with a fragment of root in spring or autumn. It can also be done with cuttings of half-ripened wood in July, inserted in sand in a closed frame, or by means of soft cuttings made from young growths in spring and rooted in a warm greenhouse.

A Guide About Echium Flower


Numerous echium species are weeds that no one would dream of cultivating in the garden. One of these, however, Echium vulgare, Viper's Bugloss or Blueweed, is a very common not unattractive biennial widely diffused throughout Europe, with its natural habitat extending up to a height of It is sometimes grown in gardens, from seed sown in the flowering position, in full sun, in April, and it is appreciated for the intensity of its blue flowers.
The common name, Viper's Bugloss, confirms the opinion of botanists who named the genus Echium, from the Greek echis this name was probably chosen because the corolla, with its protruding, forked appearance, resembles a serpent's head. The genus is native to the Mediterranean regions and Southern Europe. It comprises several annual and biennial species that are of particular
value for their lovely blue and pink flowers. There is also a shrubby species, Echium fastuosum, a truly magnificent, spectacular plant. Visitors to the famous Hanbury Botanic Garden in La Mortola, Italy, can see it in all its glory because there it is grown to perfection on a large scale. In England it is practically impossible to cultivate this superb plant out of doors, while in the United States its outdoor cultivation is restricted to almost frost-free areas such as southern California; it can also be grown in a temperate greenhouse. It is, however, a difficult, capricious plant and not a subject recommended for the amateur.
The herbaceous perennial species and their varieties can be propagated from seed sown in frames in March; the annuals should be sown directly into their flowering positions in April; while Echium fastuosum can be propagated from cuttings in July and rooted in a closed greenhouse.
Echium fastuosum Ait.
Native to the Canary Islands. An evergreen shrub that will not tolerate frost and requires a warm, sunny position in well-drained alkaline  soil. When not in flower the plant is a somewhat ungainly shrub with greyish-green foliage. The inflorescences are spectacular, resembling very large erect candles, and are composed of masses of small, closely packed heads of beautiful, intense Mediter-ranean-blue flowers. Plants raised from seed have a tendency to vary in colour intensity, and it is essential to propagate from cuttings taken from the best-coloured plants.
Echium plantagineum L.
Native to Southern Europe. A very beautiful hardy annual species with lilac-blue flowers borne on compact plants. It is very free- flowering and can be used effectively for massing in beds or borders, although in a hot climate the flowering period is of relatively short duration. A particularly colourful strain is the var. Blue Bedder, which can also be effectively grown as a pot plant. A mixture of the variously coloured hybrids, which includes blue, pink, violet, and white, is sold under the name of Echium plantagineum hybrids. Any ordinary fertile soil is suitable, in a hot, sunny, moderately dry position.
Echium wildpretii Pearson
Native to Teneriffe in the Canary Islands. It is a pity that this species is not hardy, and only suitable for frost-free climates. There, however, it provides spectacular effects. The plants will bloom the second year after seed is sown, sometimes even the first year. When not in flower, the low-growing plants are not too attractive, but when the tall, erect,high flower spikes appear, they form a column of beautiful pink flowers. When well cultivated in a suitable climate this is a superb plant requiring an alkaline soil and an abundance of warmth and sunshine.

Tuesday, June 19, 2012

A Guide About Dolichos Flower


These plants are native to the tropics and members of the pea family. The best-known garden species, and certainly the most ornamental, is Dolichos Lablab which—using a non-scientific term but giving the plant a description easily understood by all—is one of the few "beans" cultivated for ornamental purposes. In some tropical countries dolichos pods are also used for food, while in the United States the plants are cultivated as fodder.
Altogether, there are about fifty species diffused throughout the tropics and the Old World. The only other species grown in gardens is Dolichos lignosus.
Cultivation. Like all vigorous fast-growing climbers, dolichos require a rich soil and they need an abundance of organic fertilizer, preferably in liquid form, during their growing season. They also need an alkaline soil, and when growing them in acid soils lime should be added. Seed should be sown in April, seeds pot in an unheated greenhouse or coldframe. When the seedlings are about, high, after eliminating the two weakest ones from each pot, they can be planted out in their flowering position, taking care not to break the root ball. If fibre pots are used, the matter of planting is simplified as the pots can be planted along with the plants. In warm climates the seeds can be sown in the open ground in their flowering position, generally in early May. One should remember, however, that dolichos are of tropical origin and will not tolerate frost.
Dolichos Lablab L
Probably native to tropical Africa, but now very widely diffused. Leaves compound, trifoliate, with each section ovate but unequal in size. The leaves have considerable beauty, green with the veins and stalks violet-red. The flowers are also very attractive, borne in racemes and looking like miniature wisterias, violet-purple and scented. The seed pods are a darker violet-purple and also fragrant. It is a climber of surprisingly rapid development and is thus of great value for covering pergolas or summer-houses, wire netting, trellises, etc. It can be effectively alternated with morning glories or Thunbergia alata. Unlike the morning glories, which bloom only at certain hours, dolichos flowers remain open at all times. Among the varieties of Dolichos Lablab there is the var. albus with cream-white flowers and with leaves, stalks, and pods entirely green; and var. giganteus, of more vigorous growth and larger proportions, with bigger flowers. There is also a shrubby dwarf form.
Dolichos lignosus L.
Very similar to Dolichos Lablab, with pinkish-purple or white flowers and smaller leaves. In the United States, in Arizona and California it is used for the same purpose as Dolichos Lablab, but it has the advantage of being evergreen and really perennial, forming a true woody climbe. Originally it was native to tropical Asia, but it is now widely diffused and a most useful evergreen climber for gardens in mild climates.

A Guide About Cuphea Flower


Grown as a summer-flowering annual, cupheas require a minimum of attention. Once established, they do not even have to be sown, as they reproduce themselves from self-sown seed in the greatest profusion where they were cultivated the previous season. The flowers are graceful, with red, tubular, unusually shaped corollas. The leaves are lanceolate, opposite, and entire. Particularly effective results can be obtained by associating cupheas with dwarf blue ageratums, dwarf yellow-flowered snapdragons, or with the silver- leaved Senecio maritima. The genus Cuphea comprises about two hundred species native to South America; only two are normally cultivated as summer-flowering annuals, the species C. ignea and C. Llavea. The name Cuphea comes from the Greek kyphos and probably refers to the curved, humped form of the seed capsule. In gardens the plants should be massed and grown like other annuals, in beds, borders, for edging and also for cultivation in pots or receptacles. Germination is easy and development is never capricious. The flowering period is very long and the plants thrive in any normal garden soil that is not excessively wet. Although they are sun-lovers, good results can be obtained from planting in partial shade, but the plants require a long, hot, sunny summer.
Cuphea ignea Lem.
Native to Mexico. Flowers solitary, axillary, scarlet, tubular, long, and conspicuous, with a black mark at the mouth of the tube. Particularly suitable for cultivating massed in beds. Leaves lance-shaped, long. Often grown as a pot plant for greenhouse use.
Cuphea Llavea Lex.
Native to Mexico. Flowers coral-red, tubular, borne in racemes. Leaves oval-lanceolate, long. The plant is slightly hairy and has a compact, shrubby, much-branched habit. The var. Firefly has flowers of a more intense red. There is also a rare white-flowered form.

Winter- and Spring flowering Species


Crocus aureus Sibth. & Sm.
Native to Greece, Rumania, and Asia Minor. The large, tall, slender flowers are rich brilliant orange-yellow and appear with the first leaves. This is a parent to many varieties.
Crocus biflorus Mill.
Native to Asia Minor and Italy. Medium-sized flowers appear with the leaves ; white, mauvish white, and striped with purple or blue. There are many lovely varieties.
Crocus chrysanthus Herb.
Native to Greece and Asia Minor. Yellow or orange-yellow, globose, medium-sized flowers, appearing before the leaves. Parent of at least twenty-five superb garden hybrids.
Crocus imperati Tenore
Native to central Italy. Named after the sixteenth-century Italian botanist Imperato. Large globose flowers produced before the leaves, with a diameter up to when fully expanded. Externally the petals are yellowish, veined with purple, while internally they are a pale lilac, veined with dark purple. This species requires a drier, sunnier position than other crocuses.
Crocus korolkowi L.
Native to Turkistan. Leaves appear simultaneously with, or slightly after, the flowers. The latter are fragrant, , long and golden- yellow with a darker centre.
Crocus sieberi Gray
Native to the island of Crete. An exceptionally beautiful species with medium-sized globose flowers that appear simultaneously with the foliage. The flower throat is orange and the petals are purple. This is a parent to many fine garden varieties, of which one of the most beautiful is var. versicolor with pale-lilac flowers and a long conspicuous orange-scarlet stigma.
Crocus susianus Ker-Gawl.
Native to southwestern Russia and the Crimea. The leaves and flowers appear simultaneously. One of the smallest-flowered species, but one of the most attractive for its vivid colouring. Petals brilliant orange, vertically striped externally with mahogany lines. Should be planted in masses, when its English common name, Cloth of Gold, can be fully understood and appreciated. Maximum height.
Crocus totnasinianus Herb.
Native to Dalmatia. Flower colour varies from blue to pinkish mauve and the flowers appear with the leaves. The blooms are long and narrow.
Crocus vernus Boiss. & Heldr.
Native to central France. Flowers and leaves appear simultaneously. The flower colour varies from white to purple, but is most frequently silver-grey or lilac with the petals generally striped purple.
Autumn-flowering Species
Crocus byzantinus L.
Native to Europe. One of the most widely cultivated species, frequently listed under the name Crocus iridiflorus. Leaves wider than the other species and without the characteristic white longitudinal stripe. The flowers are also different from most of the other species, resembling a small iris. Flowers appear before the leaves, and are long. The petals are purple-blue externally while the shorter internal petals are pinkish mauve suffused with silver.
Crocus kotschyanus Koch
Native to Asia Minor. This widely cultivated species has produced a great many garden hybrids. Of very vigorous habit and one of the best species for naturalizing. Flowers large, pinkish lilac with an orange mark at the base of each petal. The flowers appear before the leaves.
Crocus longiflorus Raf.
Native to central and southern Italy, and Malta. Flowers fragrant and produced before the foliage. Blooms large, globose, lilac externally, pinkish mauve internally, with an orange throat. Very conspicuous dark-orange stigmata.
Crocus sativus L.
Native to Central Europe and Asia Minor. Flowers and foliage appear together. Large generally lilac-purple flowers, but variable in colour. Long, conspicuous, orange-red stigmata, from which saffron is obtained.
Crocus speciosus Bieb.
Native to Eastern Europe, Asia Minor, and the Caucasus Mountains. One of the most important species. with large elongated globose flowers that vary in colour from blue to lavender to bluish white. The blooms appear before the leaves. There are many varieties, several of which are:
var. Aitchisoni, very large lavender-blue flowers
var. Oxonian, intense blue
var. Pollux, violet-blue and silver
Crocus Hybrids
These garden hybrids are more widely cultivated than the species. The flowers are large, conspicuous, and brightly coloured, but they do not possess the elegance, grace, or charm of the smaller-flowered species. The flowers appear at the same time as the leaves in early spring. Their dormant period begins in June. Their range of colours is vast and includes white, purple, orange, yellow, or pinkish mauve, while many have striped or variegated petals. They produce abundant seeds  and naturalize freely. The best planting time is September— October and, except that they are more tolerant of sun, the cultural requirements are the same as for the species.