Imagens das páginas
PDF
ePub

plants can only be maintained by this means. In this case cuttings may be taken to the extent required immediately before the summer occupants claim their quarters, and the old plants be turned on the rubbish-heap, or utilised in any other way.

A. argenteum (Silvery-leaved Madwort).—This is a compactgrowing species, with small oblong leaves, broader at the point than the base, silvery on the under side, and dotted above with minute starry grey hairs. Flowers in dense panicles, yellow, appearing in April and May. Native of Piedmont and Corsica, in exposed rocky places. Best fitted for culture on rockwork, and succeeds but indifferently in the open ground, where the soil is naturally moist. Height 9 inches to 1 foot.

A. gemonense (Austrian Madwort).—This is a splendid sort, of shrubby diffuse habit, with large lanceolate leaves, hoary on both surfaces, the margin marked with a few obscure teeth. The flowers are produced in great profusion in April, May, and June, and are very conspicuous in masses at a distance, being bright golden yellow, This is the most valuable of all the spring yellow bedding plants, being superior to the ordinary form of A. saxatile in vigour, colour, and profusion of bloom. It grows well everywhere, and in a variety of soils, and is quite hardy, but prefers light dry loam. Where the ground is wet, little hillocks should be raised to plant upon, in order to secure immunity from the effects of stagnation. It may be naturalised on dry banks in semi-wild places with ease, if rabbits do not abound in the place; but need not be attempted if they do, as they are partial to the plant in a strong degree.

A. saxatile (Rock-Madwort):-—Botanists are not at one with each other regarding the distinctness of this plant from A. gemonense, and the strongest opinion appears to be favourable to regarding the latter as a variety of the Rock-Madwort. The two forms are, however, quite distinct for horticultural purposes in large collections; but in smaller, only one may be recommended—and in that case A. gemonense should be preferred, as being the most beautiful, and adaptable to a greater variety of uses.

A. saxatile is, however, equally well fitted for naturalising on dry banks and about the walls of ruins, where a little soil may be introduced for it to grow in. Height about 9 inches. Native of many countries of S. Europe and W. Asia. Flowers about the same time as A. gemonense. A variegated form of this species may or may not be considered valuable, according as taste in these things sways one. My own opinion is that it is worthless; the contrast between the hoary groundcolour and the creamy-white margins is not sufficiently distinct;

and the variegation has the effect also of depreciating the beauty of the flowers, which is very obvious when the two sorts are grown side by side. ·

Arabis (Rock-Cress).—This is a rather numerous family, and presents a greater variety of colour in its species than Alyssum; but I do not think a more extensive selection would be proper, for though easily-managed hardy plants, only two or three species are far enough removed from weediness to be admitted among ornamental plants. Those included in the following selection are very easily cultivated, thriving in most soils and in almost any situation. They are, however, most characteristic of rockwork; and even when grown in borders and other flat surfaces have the best effect when raised in hillocks. They are of more straggling growth, if A. lucida is excepted, than the Alyssums, and require a little more attention where trimness and smoothness of surface are required; but the pegging necessary to secure this object may be turned to account for the purpose of increase, as by this means alone, owing to the tendency of all the species to strike root from their trailing stems into the ground, if they are kept firmly attached to it, a larger increase may be obtained in one season from a plant than by means of cuttings or division. Cuttings, if they should be resorted to for increase, require the same treatment as has been already noticed for Alyssum, only the bell-glass is not so indispensable. They must be taken as soon as growth is active; and as they are of an unhandy style—always top-heavy-in the case of the species of the albida type, as much of the flexible cord-like stem should be taken along with the rosette of leaves as is convenient, in order to provide means of fastening the cutting securely in the soil. Seeds also may be used sown out of doors in any spare spot, but only the specific forms may be raised in this way with certainty; the variegated varieties do not come true.

A. albida, syns. A. caucasica and A. crispata (Sicilian RockCress).—This is the best known, and one of the best, of the samily. The plant forms diffuse patches of running stems, clothed at the extremities with rosettes of pale-green leaves, wavy and toothed on the margins, and clothed with greyish hairs. Flowers white, in profuse loose panicles about a foot high, appearing in greatest profusion from March till June, but flowering more or less earlier and later than those months. A most valuable plant for spring flower-gardening, for rockwork, for the mixed border, and for naturalising on dry banks, about ruins, and in open woods. The variety named A. albida variegata is a beautiful and useful plant for purposes of edging and

massing in the flower-garden. There are two distinct forms of this; one with the variegation white, and the plant more weakly and small in all its parts—in the other, the variegation is yellowish or sulphur, and the plant more robust: both are useful, but the smaller-growing plant is the more elegant of the two. Native of Sicily, Greece, the Caucasus, and other parts of Russia. A. alpina Alpine Rock-Cress)

.This form does not differ much from A. albida, except in respect of freeness of growth, in which it is inferior to that species, and in the smaller size and closer toothing of the leaves. The flowers are equally profuse and white, and appear from March till June, but it is less disposed to flower either before or after those periods. Enjoys a very wide distribution on the Alps, and affects a variety of habitats, but chiefly stony places.

A. blepharophylla (Californian Rock-Cress). This species is of recent introduction. It is nearly allied to A. albida, having the same mode of growth and similar character of foliage; the flowers, also, are of the albida type, and are of a rosy-purple colour. The flowers appear in May and June. Best adapted for culture on rockwork, but in dry warm soils will likely prove hardy in most parts of the country in the open border. Height about 9 inches. Native of California.

A. lucida (Shining Rock-Cress).—The species in this case is of much less ornamental value than the variety named A. lucida variegata, which is undoubtedly one of the handsomest of hardy yellow variegated plants at present in cultivation. The plant grows in close tufted habit, producing close rosettes of shining dark-green leaves beautifully margined with bright yellow. About 4 to 6 inches high. The flowers are white, but should not be allowed to appear in the variety, as the foliage becomes injured thereby. The normal form is a pretty plant on rockwork, being very neat and compact in growth. Native of Hungary

A. procurrens (Procurrent Rock-Cress). — This is a pretty, smooth-growing, prostrate plant, with entire, shining, almost linear leaves, entire on the margins. Flower largish, pure white, rather profuse, appearing in April, May, and June. Height 6 to 9 inches. I have grown this plant for greenhouse decoration in shallow well-drained pots, and found it most useful in the end of February and throughout March for ornamenting front stages. A very pretty variety with variegated leaves is not very plentiful in gardens, but it is a beautiful plant, and should be more popular once it is more widely known than it is at present. Native of Carniola and Hungary. Easily pro

pagated by cuttings in early summer, and by division in autumn or winter.

Aubrietia.—A very interesting and attractive genus, of few species so called, but which are not strikingly distinct in character one from the other. They are all, however, worthy of cultivation, though not together in one collection, except perhaps in the largest; but no collection of spring flowers may be considered complete without one or other of their best forms in its ranks. The same spreading trailing manner of growth, and the same rosette style or crowding of the leaves at the extremities of the stems and branches, as characterise the RockCresses of the albida type, are characteristic of these little plants, but in miniature only, the plants being less vigorous and bold, and when managed well in a congenial situation and soil they become most beautiful objects. They are best adapted for culture on rockwork, their low carpet-like growth being invaluable for that kind of ornamentation. They succeed in all light loams freely in any situation ; but very indifferently, and often fail entirely, in heavy wet soils. In beds and borders, in soils of the unfavourable kinds, they should be raised above the surface-level by some means, so as to secure that comparative dryness and freedom from stagnation they like so well. A very good plan, in heavy loam and clay, is to make a pit to the extent the plant is designed to occupy, and about half the depth of a spade, filling in with stones, brick-rubbish, or rough charcoal to the surface-level, finishing up with a mound of good loam and leaf-mould on the top of the drainage, about 6 inches deep, on which to plant. The better forms of these plants are worth any amount of trouble that may be necessary to secure their wellbeing; and those who succeed will not regret any tax that may have been temporarily laid upon them, when they come to enjoy the rich beauty they so freely and continuously yield at a period of the year when flowers in profusion are comparatively rare. Their brilliant dense masses of flowers are being turned to excellent account in spring bedding, or massing in flower-gardens. Propagation may be effected by cuttings in early summer in a shady place, by division in autumn or early winter, and by seeds sown as soon as ripe in a cold frame or under a hand-glass, the plants to be pricked carefully off into rich light soil as soon as they can be handled.

A. Campbellii (Campbell's A.)—This is comparatively a new form, and is probably of garden origin. It is the most brilliant of the group, forming dense carpet-like patches of pale-green foliage, which is profusely covered with comparatively large light violet-purple flowers from March till June.

A. deltoidea, syn. Farsetia deltoidea.—This is an old inhabitant of gardens, and though decidedly inferior in showy qualities to the preceding and other varieties, is no mean plant in its season. It is less luxuriant than Campbell's A., and the flowers are smaller and pale purplish blue, but very abundant, appearing about the same time. The varieties A. d. grandiflora and A. d. græca are distinguished only by greater size and brilliancy of colouring, and are simply more valuable where these qualities are essential in the highest degree. They are all valuable plants for town gardens; for, except that their natural brightness does not appear to the greatest advantage in a smoky atmosphere and amid smutty surroundings, there are few alpine plants that can accommodate themselves with more facility to conditions so opposite to those of their native homes. A. deltoidea is a native of the Levant.

Barbarea.—In the natural state none of the species of this genus are fit for ornamental purposes, but there are two varieties of B. vulgaris-an indigenous species—which are worthy of cultivation in any garden.

B. vulgaris flore - pleno, syn. Erysimum barbarea florepleno (Double-flowered Winter-Cress, or Yellow Rocket). — This is a beautiful and curious plant. The process of doubling is very peculiar in the flowers; I am not aware of any parallel to it in other double flowers. There appears to be no attempt made at any time to form either stamens or pistils. But the axis of the flower has the power of extending itself and producing numerous whorls of petals as it grows in length, and assumes the appearance of a narrow cylindrical spike. A very lengthened succession of flower is kept up both by this peculiar extension of the axis, and by the natural process of development of the inflorescence, which is open, but rather rigidly panicled. Height about 18 inches. Flowers bright yellow, appearing from June till late summer, and often into autumn. B. vulgaris is a native of many parts of Britain, and this peculiar variety is probably an accidental production of nature or of cultivation. It is an excellent ornament of the mixed border, succeeds in almost any kind of soil, but prefers a rich moderately - light loam. Propagate by division of the rootstock.

B. vulgaris variegata (Blotch-leaved Winter-Cress).—This is the simple form of the species with yellow blotched leaves. The leaves are pinnate, the leaflets small on each side of the stalk, but the terminal one is generally very large, and in this variegated form is very conspicuous. The plant is interesting only as a variegated subject; the flowers are worthless, and

« AnteriorContinuar »