App. VI. Culture of the hardy and half-hardy Species and Varieties of Ericea belonging to the Group Ericeæ normales. The hardy Species of Ericeæ normales are most commonly propagated by layering the branches in very sandy peat. The shoots require no cutting or twisting; but, if they are buried in the soil, about 1 in. deep, and to within 1 in. of their points, and the soil be kept firm and moist over them, they will root freely in two or three months, in the spring or autumn. Layers made in October or November will be fit to take off in the following May or June; as will layers made in February or March. Some of the commoner heaths are also propagated by division, or detaching stems or branches which may have produced roots; and all the species may be raised from seeds when these ripen. The soil in which all the species and varieties thrive best is sandy peat, though some of the species will thrive with a greater proportion of loam intermixed with the peat than others. Whatever soil is used, it ought to be mixed with pieces of freestone or brickbats, as reservoirs of moisture, and placed on a stratum of gravel, as drainage, for reasons which will be hereafter mentioned. A Heathery, or Ericetum, in the open Ground is justly considered as one of the most interesting ornaments of the flower-garden or pleasure-ground, from its being at all times green, and exhibiting plants in full flower during every month in the year. Perhaps the most complete hardy heath garden in England is that at Woburn Abbey. There, Mr. Forbes informs us, "Each species or variety is confined to a separate bed, the beds being edged with the Calluna vulgàris and Erica Tétralix; and so disposed, that the tallest-growing kinds are arranged towards the centre of the parterre: whilst the whole are so intermixed, in point of colour, as to produce the most lively contrast possible." (Hort. Wob., p. 282.) A plan of the parterre for hardy heaths is given in the Hortus Woburnensis, exhibiting upwards of 70 groups; but, as the distribution of the species and varieties, among these groups, so as that the tallest-growing kinds may be "arranged towards the centre," and the whole so intermixed in point of colour as to produce the most lively effect possible," is not given in the Hortus Woburnensis, we have written to His Grace the Duke of Bedford, to request that he would authorise Mr. Forbes to supply us with so interesting a desideratum. In every case, the shapes and sizes of the beds of a parterre, especially one to be planted with ligneous plants, which may be considered fixtures, are of trifling consequence in comparison with the arrangement of the plants in them. We have been the more anxious to indicate this arrangement, in the case of the Woburn ericetum, because the late Mr. George Sinclair, F.L.S., who designed the beds, and, we presume, planted them, had a scientific knowledge of, and an excellent taste in, colours. His arrangement of the heaths in these beds, therefore, so as to produce a harmonious effect, we consider to be of great interest to gardeners intending to plant a heathery; and we are happy in being able, through the kindness of the Duke of Bedford, to lay it before our readers. The hardy ericetum at Woburn Abbey is situated in front of the Cape ericetum, and the form of the beds is exhibited in fig. 886. In this figure, a is the passage under the Cape heathery, which forms a portion of a covered way, leading from the mansion to the different objects of interest adjoining it; such as the green-house, sculpture gallery, tennis-court, Chinese dairy, plant-stoves and palm-house now erecting, and finally to the pleasureground, including the aviary, arboretum, salictum, grass-garden, American garden, &c. b is a broad gravel walk; being a portion of the main walk of the pleasureground. c, Descent from the porch of the Cape heathery. d, Shrubbery, chiefly consisting of rhododendrons and azaleas. 1 to 73, Heaths, and other Ericàceæ, arranged as in the following list. 1, Gypsocállis (Erica) vàgans álba. 2, Erica cinèrea. 3, Phyllódoce taxifòlia (Menzièsia cærùlea). 4, Azalea procumbens. 5, Erica austràlis. 6, Gypsocallis (E.) mediterránea. 7, Erica cinèrea álba. 8, Erica scopària. 9, Erica cinèrea atropurpurea. 10, Cape heaths. 11, Phyllódoce taxifòlia (Menzièsia cærulea). 12, Dabo cia poliifòlia álba (Menzièsia). 13, Cape heaths. 36, Gypsocállis (E.) cárnea. 40, Cape heaths. 41, Callùna (E.) vulgàris flòre plèno. 46, Erica cinèrea atropurpurea. 48, Gypsocállis (E.) vàgans pállida. 50, Erica floribúnda. 14, Dabo 'cia poliifòlia nàna (Men- 51, Cape heaths. zièsia). 15, Erica ciliàris. 16, Erica Actæ a. 17, Gypsocállis (E.) vàgans rùbra. 18, Cape heaths. 19, Callùna (E.) vulgàris spicata. 20, Dabo cia (Menziesia) poliifòlia. 21, Gypsocállis (E.) mediterrànea. 22, Cape heaths. 23, Erica viridipurpùrea. 24, Gypsocállis (E.) vàgans álba. 25, Erica arborea. 26, Callùna (E.) vulgàris álba. 27, Gypsocállis (E.) mediterrànea. 28, Erica stricta. 29, Erica scopària mínima. 30, Erica cinerea atropurpurea. 31, Erica austràlis. 32, Gypsocállis (E.) cárnea. 33, Azalea procumbens. 34, Erica scopària. 35, Gypsocállis (E.) vàgans tenélla. 52, Empetrum nigrum. 54, Callùna (E.) vulgàris spùria. 58, Erica arbòrea. 59, Erica austràlis. 60, Callùna (E.) vulgàris variegata. 63, Erica viridipurpurea. 66, Gypsocallis (E.) cárnea. 69, Gypsocállis cárnea herbàcea. 72, Gypsocállis cárnea herbàcea. In order to study the effect, in point of colours, which this ericetum will have in every month of the year, we recommend the reader of leisure, and more especially the young gardener, to make 12 copies of fig. 886., and then to look at App. II. (p.1088.), and observe the sorts of heath which will be in flower in each month of the year, their colours, and their heights. Then let him take the copy of the plan of the ericetum for January; and, as he will find by the list, App. II., that there will be only two sorts in flower during that month, viz. Gypsocállis cárnea and G. c. herbàcea, both of which have pink flowers; let him colour with pink all the beds indicated to be planted with that sort, colouring all the other beds green. This will give 8 red beds and 65 green ones for the month of January. To indicate the height which the plants in each bed are supposed to attain, the height of each sort, as indicated in the list, may be taken from the scale; and each bed drawn in isometrical projection, as shown in fig. 887., which is supposed to represent bed No. 21., intended to be planted with Gypsocallis mediterrànea, a species estimated to grow to the height of 4 ft. Whether the operation of colouring is performed on a ground plan, such as fig. 886., or on an isometrical view to show the height, prepared after the manner described, the colouring ought to be applied from the list 887 in App. II. to twelve different copies of the plan, so as to show the appearance which the ericetum will have, or ought to have, in every month of the year. We know that in practice it is impossible to attain to perfection in matters of this kind; but still it is highly advantageous to proceed upon sound principles, and to have a beau idéal of the effect to be produced in view. For this reason, we recommend gardeners, when they are forming a scheme for planting a flower-garden, always to try the effect which it will have during the principal summer months, by drawing a plan for each of these months, and colouring the beds in each with the colours of the flowers of those plants which are intended to be simultaneously in bloom. Such coloured plans being shown to the employers (and more especially to the female part of the family, who have generally considerable taste in the arrangement of colours), useful hints may be received, and the beds altered until perfect harmony is produced. Another mode, and one which would afford an excellent exercise for young gardeners, would be for the gardener to lay before his employers, once in every year, twelve copies of the plan of his flower-garden (for which purpose it might be lithographed), and these copies being coloured by the lady of the family agreeably to her taste, or ideas of what constitutes harmony, the problem for the gardener to solve would be: "Required, the kinds of plants, and the modes of treating them, necessary to produce the given colours in the given months." Of course, the plans and this problem for every year would require to be given to the gardener a year before the time when it was intended to be carried into execution, in order that he might have time to prepare and propagate the requisite kinds and numbers of plants. These remarks, though apparently not immediately applicable to ericetums, or flower-gardens composed of hardy heaths, are yet decidedly so when Cape heaths are included; and they are also applicable to gardens of low American shrubs, including azaleas, rhododendrons, &c., such as will be hereafter treated on and described. A symmetrical Ericetum. The hardy ericetum at Woburn Abbey is of an irregular shape, because it is adapted to a particular situation; and the surface being a bank, sloping towards the house containing the Cape heaths, it is seen to most effect when walking along the covered way (a); but, where an independent ericetum is to be formed, we would recommend a level surface sunk 2 ft. or 3 ft. below a surrounding walk; and we would further advise, as a desideratum in all hardy ericetums, that all the narrow walks between the beds be paved with pebbles, brick, stone, or some other perfectly smooth surface. The reason is, that when the path is of gravel or sand, the small delicate foliage and flowers of the heaths, which rest almost on the ground, are soiled and disfigured with the sand and lighter particles of gravel, after every heavy shower. Fig. 888. is such a plan as we would recommend. The sectional line (a b) shows that the beds are sunk about 3 ft. below the surrounding terrace walk. From this walk the beds are separated by a sloping bank, the upper and lower verges of which may be of turf, and the middle part may be planted with that variety of heath which comes into flower at the season when it is desired that the ericetum should look most gay. Thus, for the ericetum of a winter or spring residence, it may be planted with Gypsocállis cárnea; and, for a summer residence, it may be planted with Calluna vulgaris, or Erica cinèrea atropurpurea. In particular soils and situations, the whole of this bank, as well as the verges, may be of fine turf, or of rockwork, planted with heaths. The descent to the beds, from the surrounding gravel walk, is by six steps. The manner in which the beds are proposed to be planted is very simple. The centre bed is to be occupied solely with species exceeding 3 ft. in height, the tallest-growing kinds being placed in the centre of the bed. Each of the other beds is to be filled with heaths which never exceed 3 ft. in height; every bed being limited to heaths which come into flower in the same month.. In fig 888., one half of the beds are numbered, to show how this is done. Thus, the beds marked 1 and 12, of which there will be six in the ericetum, will be wholly occupied with Gypsocállis |