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GERANIUM
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GERANIUM , the name of a genus of See also:plants, which is taken by botanists as the type of the natural See also:order See also:Geraniaceae. The name, as a scientific appellation, has a much more restricted application than when taken in its popular sense. Formerly the genus Geranium was almost conterminous with the order Geraniaceae. Then as now the geranium was very popular as a See also:garden plant, and the See also:species included in the See also:original genus became widely known under that name, which has more or less clung to them ever since, in spite of scientific changes which have removed the larger number of them to the genus Pelargonium. This result has been probably brought about in some degree by an See also:error of the nurserymen, who seem in many cases to have acted on the conclusion that the See also:group commonly known as See also:Scarlet Geraniums were really geraniums and not pelargoniums, and were in consequence inserted under the former name in their See also:trade catalogues. In fact it may be said that, from a popular point of view, the pelargoniums of the botanist are still better known as geraniums than are the geraniums themselves, but the See also:term " zonal Pelargonium " is gradually making its way amongst the masses. The species of Geranium consist mostly of herbs, of See also:annual or perennial duration, dispersed throughout the temperate regions of the See also:world. They number about 16o, and- See also:bear a considerable See also:family resemblance. The leaves are for the most See also:part palmately-lobed, and the See also:flowers are See also:regular, consisting of five sepals, five imbricating petals, alternating with five glandules at their See also:base, ten stamens and a beaked ovary. Eleven species are natives of the See also:British Isles and are popularly known as See also:crane's-See also:bill. G. Robertianum is See also:herb-See also:Robert, a See also:common plant in hedgebanks. G. sanguineum, with flowers a deep See also:rose See also:colour, is often grown in See also:borders, as are also the See also:double-flowered varieties of G. pratense. Many others of See also:exotic origin See also:form handsome border plants in our gardens of See also:hardy perennials; amongst these G. armenum, G. Endressi, G. ibericum and its variety platypetalum are conspicuous. From these regular-flowered herbs, with which they had been mixed up by the earlier botanists, the See also:French botanist L'Heritier in 1787 separated those plants which have since See also:borne the name of Pelargonium, and which, though agreeing with them in.certain points of structure, differ in others which are admitted to be of generic value. One obvious distinction of Pelargonium is that the flowers are irregular, the two petals which stand uppermost being different—larger, smaller or differently marked—from the other three, which latter are occasionally wanting. This difference of irregularity the See also:modern florist has done very much to annul, for the increased See also:size given to the flowers by high breeding has usually been accompanied by the enlargement of the smaller petals, so that a very near approach to regularity has been in some cases attained. Another well-marked difference, however, remains in Pelargonium: the back or dorsal sepal has a hollow See also:spur, which spur is adnate, i.e. joined for its whole length with the See also:flower-stalk; while in Geranium there is no spur. This peculiarity is best seen by cutting clean through the flower-stalk just behind the flower, when in Pelargonium there will be seen the hollow See also:tube of the spur, which in the See also:case of Geranium will not be found, but the stalk will appear as a solid See also:mass. There are other characters which support those already pointed out, such as the See also:absence of the glandules, and the See also:declination of the stamens; but the features already described offer the most ready and obvious distinctions. To recapitulate, the geraniums properly so-called are regular-flowered herbs with the flower-stalks solid, while many geraniums falsely so-called in popular See also:language are really pelargoniums, and may be distinguished by their irregular flowers and hollow flower-stalks. In a See also:great See also:majority of cases too, the pelargoniums so commonly met with in greenhouses and summer parterres are of shrubby or sub-shrubby See also:habit. The various races of pelargoniums have sprung from the intermixture of some of the species obtained from the Cape. The older show-flowered varieties have been gradually acquired through a See also:long See also:series of years. The See also:fancy varieties, as well as the French spotted varieties and the See also:market type, have been evolved from them. The zonal or bedding See also:race, on the other See also:hand, has been more recently perfected; they are supposed to have arisen from hybrids between Pelargonium inquinans and P. zonale. In all the sections the varieties are of a highly ornamental See also:character, but for See also:general cultivation the market type is preferable for indoor purposes, while the zonals are effective either in the greenhouse or flower garden. Some of the Cape species are still in cultivation—the leaves of many of them being beautifully subdivided, almost See also:fern-like in character, and some of them are deliciously scented; P. quercifolium is the See also:oak-See also:leaf geranium. The See also:ivy-leaf geranium, derived from P. peltatum, has given rise to an important class of both double- and single-flowered forms adapted especially for pot culture, See also:hanging baskets, window boxes and the greenhouse. Of See also:late years the ivy-leaf " geraniums " have been crossed with the " zonals," and a new race is being gradually evolved from these two distinct See also:groups. The best See also:soil for pelargoniums is a mellow fibrous See also:loam with See also:good well-rotted See also:stable manure or leaf-See also:mould in about the See also:pro-portion of one-fifth; when used it should not be sifted, but pulled to pieces by the hand, and as much See also:sand should be added as will allow the See also:water to pass freely through it. The large-flowered and fancy kinds cannot bear so much water as most soft-wooded plants, and the latter should have a rather lighter soil. All the pelargoniums are readily increased by cuttings made from the shoots when the plants are headed down after flowering, or in the See also:spring, when they will See also:root freely in a temperature of 65° to 9o°. They must not be kept too See also:close, and must be very moderately watered. When rooted they may be moved into well-drained 3-in. pots, and when from 6 to 8 in. high, should have the points pinched out in order to induce them to push out several shoots nearer the base. These shoots are, when long enough, to be trained in a See also:horizontal direction; and when they have made three See also:joints they should have the points again pinched out. These See also:early-struck plants will be ready for shifting into 6-in. pots by the autumn, and should still be trained outwards. The show varieties after flowering should be set out of doors in a sunny spot to ripen their See also:wood, and should only get water enough to keep them from flagging. In the course of two or three See also:weeks they will be ready to cut back within two joints of where these were last stopped, when they should be placed in a See also:frame or See also:pit, and kept close and dry until they have broken. When they have pushed an See also:inch or so, turn them out of their pots, shake off the old soil, See also:trim the straggling roots, and repot them firmly in smaller pots if practicable; keep them near the See also:light, and as the shoots grow continue to See also:train them outwardly. They require to be kept in a light See also:house, and to be set well up to the See also:glass; the See also:night temperature should range about 450; and See also:air should be given on all mild days, but no See also:cold currents allowed, nor more water than is necessary to keep the soil from getting parched. The See also:young shoots should be topped about the end of See also:October, and when they have grown an inch or two beyond this, they may be shifted into 9-in. pots for flowering. The shoots must be kept tied out so as to be fully exposed to the light. If required to flower early they should not be stopped again; if not until See also:June they may be stopped in See also:February.
The zonal varieties, which are almost continuous bloomers, are of much value as decorative subjects; they seldom require much pruning after the first stopping. For See also:winter flowering,
young plants should be raised from cuttings about See also: For bedding purposes the zonal varieties are best struck towards the See also:middle of See also:August in the open air, taken up and potted or planted in boxes as soon as struck, and preserved in frames or in the greenhouse during winter. The fancy varieties root best early in spring from the See also:half-ripened shoots; they are slower growers, and rather more delicate in constitution than the zonal varieties, and very impatient of excess of water at the root. Additional information and CommentsThere are no comments yet for this article.
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