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plants on starting show any symptoms of sickness or weakness, there should be no hesitation in choosing the lesser evil, for the chances are that the plants will not survive the flowering period, and the flower-stems in such cases are rarely of any use for the purpose of propagation. Cuttings taken in the early part of the season should be chosen of rather weakly or medium strength, those that are gross and succulent being very apt to damp off; and it is advantageous to secure a small bit of the old crown at the base of the cutting. They should not be more than 3 inches long when taken off, and should be planted in very sandy soil in pots under a hand-glass out of doors or in a cold frame ; but if a spent hotbed in which a little bottomheat remains can be used, so much the better, as it will insure greater success. Those cuttings made of the flower-stems, if the plant is vigorous, are often very successful; but they must be taken immediately the first indications of the waning of the flowers are observed, as they soon become hard and lifeless, and will not emit roots. They should be cut into lengths of three or four joints, and cut clean over immediately under the lowest joint; and if very hard, the bark should be slightly scarified with the knife to the extent of 1 inch above the base of the cutting, to facilitate the callousing process, otherwise they should be treated exactly like the earlier cuttings. The later cuttings —those procured by the autumn or late summer growth that is made after flowering-are generally the most convenient, as the floral display is not in any way diminished by them ; but the system of annual propagation must be assiduously attended to in order to be able to procure the cuttings, and it is generally advantageous to stimulate the plants immediately after flowering, by pricking into the surface with a fork a little fresh loam, and light well-decomposed manure, and by copious watering if necessary. The cuttings, taken as soon as they can be got, should receive the same treatment as the spring cuttings, and they may be wintered in any sheltered warm place out of doors; but, if convenient, they are better kept in a cold pit, frame, or under a hand or bell glass, where they may be protected from battering rain and severe frost. A very cool treatment must be given them, however, under protection; air to be given in all weather except severe frost, by tilting the protection in wet or snowy weather, and removing it wholly when these do not prevail. They are also propagated by division, both the double and single varieties; but the method, though less troublesome than that of cuttings, is not so satisfactory and sure. The best time to divide is immediately after flowering is done; and if possible a showery period should be chosen in which to perform it,
otherwise close attention to watering will be necessary, and it should not be given in daily driblets, but in abundance when obviously required. The single sorts are best raised from seed sown in the open ground in March or April, the plants afterwards to be pricked out into their permanent positions. They may also be increased by division if only limited increase is required, but seed is preferable for the purpose of raising large quantities for planting out in bulk. The characteristic features of the Rockets, whether single or double, are too well known to require description. The best double varieties are the double purple Purpureo-pleno, the double white Albo-pleno, the double red Rubro-pleno, and the double variegated with purple and white blotched and striped flowers, named Variegato - pleno. There are better and worse strains of these—some loose and inclined to lankiness, and inferior in brightness of colouring, and others more compact, more double, and bright; but soil and culture exercise an important influence on these points, and aged plants generally deteriorate much, hence the necessity of keeping the stock always vigorous by assiduous periodical propagation. There are representatives of the above colours in single sorts also ; they grow about 3 or 4 feet high : the double sorts are more dwarf and compact, rarely exceeding 272 feet. The species is a native of Italy, and begins to flower about the end of May, and continues throughout the two or three following months. There are other sorts sometimes named specifically in our catalogues which are only varieties of H. matronalis : the most frequent of these is H. inodora, an almost scentless form of the species; and H. siberica, with pink flowers. Other species there are, but rare if at all to be found in our gardens nowadays, and which are not equal in any respect to the varieties of H. matronalis noticed above.
Hutchinsia.—A genus of very few species, only one of which is at present known in gardens in this country, and not so well known as it should be. H. alpina is a very dwarf compactgrowing perennial, producing deeply-pinnatifid leaves and pure white flowers in clusters, supported on stems about 2 or 3 inches high, and in considerable abundance. The flowers appear in May and June, and occasionally also in July. Although a tiny plant, it delights in a soil of considerable depth, as in deep fissures of rockwork. It is best adapted to the adornment of rockwork, and should have an open sunny position, but succeeds well also in the open border if the soil is not close and retentive. It would no doubt be useful also for edging and massing in the spring flower-garden if kept in pots in reserve for that purpose. Propagate by division after flowering is well over,
or in the autumn early, or in early spring, and by seed sown in small pots in a cold frame or where it is to remain, if a few plants in a permanent position on rockwork or open border are all that is aimed at. It is widely distributed on the greater mountains of central and southern Europe.
Iberidella rotundifolia, syns. Thlaspi rotundifolia and Iberis rotundifolia (Round-leaved 1.)—This is a little-known plant in British gardens, but deserves a place in every collection of alpine plants. It is a dwarf compact plant, with thick, leathery, slightly milky-green, roundish leaves, rather densely tufted. The flower-stems rise to the height of 5 or 6 inches bearing the flowers—which are rosy lilac with a yellow centre, and sweet-scented—in erect dense racemes. The plant is most suitable for rockwork, and succeeds best in rich gritty loam in deep fissures; being tap-rooted, it will not readily increase by division, but it is easily raised by seed sown in small pots in a cold frame, or in the spot it is designed to occupy. It is an elegant bright little plant, which should be in every collection. Flowers from May till July, and is a native of the Swiss Alps and other European alpine regions.
Iberis (Candytuft). - This is a beautiful and well-known group of hardy plants. It comprises a good many species, but among the perennials there are but a few really distinct for ornamental purposes, the others being too close in resemblance to be worthy of being cultivated, except in botanical collections. They are plants of most simple requirements in cultivation, adapted to grow in any kind of garden-soil, succeeding best in that which is light, rich, and dry, but doing very well in the debris of an old ruin, or on a dry sandy bank where not many plants would exist. If this easy habit were taken advantage of freely, many an unclothed and uninviting spot would be gracefully garnished and attractive through
Besides their great value as mixed border-plants, and for the adornment of rockwork, they are invaluable subjects for the spring flower-garden, whether as temporary occupants or permanent in a garden set apart for such plants; they are useful also for planting in shrubbery borders. Propagate by seed sown in the open ground, or better in a cold frame or handglass, and by cuttings or division, at almost any time of the growing period; but both operations are best performed either immediately after flowering is over or in early autumn.
I. corifolia, syn. I. saxatilis, var. corifolia (Coris-leaved Candytuft).—If not one of the best of the group, this is one of the dwarfest and neatest, rarely exceeding 6 inches in height, making a close carpet of bright green foliage, and producing its
out the year.
flowers in small rounded heads in great profusion in April, May, and June. Best adapted for clothing rockwork, edging, small beds, or for the front lines in mixed borders. Native of Sicily.
I. Garrexiana (Garrex's Candytuft).- This is one of the least valuable of perennial Candytufts, but one of the most commonly cultivated. It comes very near the Evergreen Candytuft, and is regarded as a variety of it; but the heads of flower are smaller, and from the tendency to elongate that the racemes have after flowering, it assumes rather a seedy aspect at the end of the flowering season. But it is nevertheless a valuable sort, being very tenacious of place once it gets a hold, and a free grower, and consequently more useful for naturalising on dry rocky places where some of the more choice sorts would not so easily establish themselves. It grows in close carpet-like masses about 6 to 9 inches high, flowers in April, May, and June, and is a native of Piedmont and Spain, and probably of other parts of Europe.
I. gibraltarica (Gibraltar Candytuft). - This is one of the most ornamental of the group. It grows from 9 inches to i foot high, in close tufted - manner, with leaves, flowers, and flower-heads considerably larger than those of any other Candytuft known to cultivation. The leaves are large, dark green, oblong, and increasing in breadth towards the point; and the flower-heads are close and broad, and have no great tendency to grow out into seedy racemes. This is a very rare plant in cultivation yet, and has not been sufficiently tried throughout the country to prove its daptability to our climate at all sea
It will be found best suited for culture on warm sheltered rockwork in sunny positions. Flowers white, shading off in age to pinkish lilac, and appearing in May and June. Native of the south of Spain.
I. Pruiti (Pruit's Candytuft).—This being undoubtedly hardy and little inferior to I. gibraltarica in point of size of flowers, and being also pure white, is one of the brightest and best of the genus. It grows about 9 inches high, producing dense masses of dark-green foliage, rather large in size, and oblong in shape. The flowers are large in compact heads, not elongating much in flowering, and appearing in May and June. Native of Naples and other southern countries of Europe.
I. sempervirens (Evergreen Candytuft). — This species is widely distributed and well known in gardens in this country. It grows in compact, carpet-like, pale-green masses, producing a great abundance of pure white flowers in small heads, which have the objectionable feature of elongating during the process of and after flowering. One of the most useful, succeeding well
in any soil and in most situations, but preferring bright sunny ones and light dry soil. It is admirable clothing for dry rocky places and sandy knolls, and luxuriates most in such places, but succeeds also well in open borders; and being very hardy, it should be planted more freely even than it is. Native of many countries of southern Europe and Asia Minor.
I. Tenoreana (Tenore's Candytuft).—From the colour of the flowers differing considerably from the other kinds, this species should become more favoured when it becomes better known and more plentiful. It resembles I. gibraltarica in its style of growth and the form of the flower-heads, which are close and compact and do not elongate, and the colour, white at first, changes to purplish red. It differs from I. gibraltarica also in being hairy in nearly every part. The blossoms are very profuse, but the plant in the true form has not been proved as regards hardiness north of the Tweed, in so far as I am aware, and should therefore be trusted out with caution in the north in winter till such time as there is ample stock in hand to cover any casualty. Native of Naples.
The only genus in this order that may with propriety be associated with herbaceous plants is Helianthemum, the RockRose. The species comprised in this genus—a large oneare, with the exception of one or two, more or less woody, being dwarf diffuse shrubs, well adapted to the purposes to which dwarf herbaceous and alpine plants are turned in ornamental gardening. It would be difficult to overpraise the beauty of the flowers of these Rock-Roses, so brilliant in colour and handsome in form are they; and it is astonishing that so few of a family so ornamental should be cultivated in our gardens. Possibly the fugaceous character of the flowers may explain why they are so seldom seen ; but the long-continued succession of flowers that may be kept up on well-cultivated young plants should be ample compensation for any defect of that kind in the individual flowers. The blooming season is often brief enough on old weak plants, but on young vigorous ones a close and profuse succession is kept up for a month or two. They offer a most promising field for the labour of the florist, not only in the way of selection, but also in hybridising. The florist has had less encouragement to undertake some of the