HANDBOOKS OF | PRACTICAL GARDENING CHARLES THONGER. Garnell University Library _ Bthaca, New York j : 1 BOUGHT WITH THE INCOME OF THE SACE ENDOWMENT FUND THE GIFT OF HENRY W. SAGE 1891 RETURN TO ALBERT R. MANN LIBRARY ITHACA, N. Y. Cornell University Library SB 453.T48B The book of rock and water gardens. Cornell University The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924002820474 - HANDBOOKS OF PRACTICAL GARDENING EDITED BY HARRY ROBERTS THE BOOK OF ROCK AND WATER GARDENS WATER LITES THE BOOK OF ROCK AND WATER GARDENS BY CHARLES THONGER ES AUTHOR OF “THE BOOK OF GARDEN FURNITURE” ‘¢THE BOOK OF GARDEN DESIGN,” ETC. ‘¢ As for our love of gardens, it is the last refuge of art in the minds and souls of many Englishmen; if we did not care for gardens, I hardly know what in the way of beauty we should care for.”— Companions oF My SOLITUDE. LONDON: JOHN LANE, THE BODLEY HEAD NEW YORK: JOHN LANE COMPANY # $ Turnbull & Spears, Printers, Edinburgh PREFACE Tuts book is written for those who love the flowers of mountain and stream, of Alpine pasture and reed-fringed pool; for those who gladly welcome into their gardens a class of plants whose beauty and charm is not surpassed by any other. It is also written with the hope that it may arouse interest in those who have no knowledge of rock and water plants, and yet have facilities for growing them. And especially is it offered to the-many whose dull and ugly “‘ rockeries” might so easily be transformed into ‘rock gardens ”—a different thing altogether. Let none regard the subject of water gardening as one having direct interest for only a favoured few. Seeing that aquatics may be grown under purely artificial conditions, the pleasure of a water garden is not limited to the possessors of natural streams and ponds. In these days of stress and hurry we seek in Nature a balm for many ills; in our gardens, and in all that pertains to them, we may find welcome rest and relaxation. Cs 7: Woonpsrince, Surro.. CONTENTS PREFACE, ‘ a : m Rock anpD ALPINE GARDENS II, Rock Garpen ConsTRUCTION : ‘ : ‘ Ill. Tue Garben oF ALPINES . A ; » . IV. Tur Rock Garven In SPRING V. Rock GarvEN Pants ; VI. Rock Suruss ¢ r . VU. Witp Water Marcins. ‘ VII. SMart WarTeR GARDENS IX. Boc anp Marsu GarpENS . P : . X. Liry Tanks . . ‘ é XI. Water-Livies . Aquatics AND Boc Piants Inpex ‘ “i . 2 : , : vii LIST OF ILLUSTRATIONS Warter-Liues . $ . ¥ . Frontispiece Rove Steps wirs SMatt Piants in Crevices . To face page 4 (Photo by Mrs Delves Broughton) Front Garpen, Brantwoop, SouTurort ‘ ‘ 3 6 Front Garpen, Brantwoon (ANoTHER View) F aa 8 Tue Epetweiss c r ‘ 4 F % 3O Putox Susutata NELsoni ‘ “ » 12 (At Messrs Barr’s Nurseries) LirgosPERMUM GRAMINIFOLIUM . i ‘ * ee c| (At the Craven Nursery, Clapham, Lancaster) Rock Garpen, LowTueR CasTLe ‘ ‘ F a» ~=—«16 Rock Garpen, Lowtuer CastLz (ANoTHER View) . » +18 Witp Garpen, Auperty Hay , P sy | 20 A Group or Dwarr IRises_. ” gy. 22 (Photo by Charles Thonger) A Rock Borper : . . . . 43: 2A (Photo by Mrs Delves Broughton) ANEMONE APPENINA . ‘ r : . « 36 (At Messrs Kelway’s Nursery, Langport) ix x LIST OF ILLUSTRATIONS Sitver SAXIFRAGES ‘4 : - . To face page 28 (At the Craven Rees! Clapham, Lancaster) Tunica SAXxIFRAGA : we). gz (At the Craven Res Bai ee Aoricutas oN Rockery a i . 3: ‘is 34 (Photo by Charles Jones) Rock GarpEN witH Grass APPROACH . ‘ re) (Photo by F. Mason Good) Rocxy Bank wits HyacinTus . , : ‘ » 38 Primuta DenticuLata ALBA. é x s op 42 Nature’s WaTER GARDEN : . : oa, be (Photo by Mrs Bice Broughton) STREAM AND Rockery IN Messrs Barr’s NursERIEs » 56 A Garven Poot . x 40 62 (Photo by F. Mason Good) Water Garpen, LowTuHer CasTLe ; ‘ é >» «=68 Arums By A LaKe-sme In CoRNWALL i 94 (Photo by S. W. Fitzherbert) Ponp wits Water-Liies, LowTHerR CasTLe . é yo 82 Iris KagMPFERI e é . . : w 36 (At Messrs Kelway’s Nursery, Langport) THE BOOK OF ROCK AND WATER GARDENS rs THE BOOK OF ROCK AND WATER GARDENS CHAPTER I ROCK AND ALPINE GARDENS BETWEEN the rock garden and the “rockery” there is a vast difference. The latter is a thing which no good gardener will tolerate, contravening as it does all ideas of common sense, good taste, and artistic perception. It is hard to preserve a spirit of tolerance towards the uncouth excrescences which distort and mar the appearance of many gardens, inflicting as they do upon the gracious earth and cool sward the semblance of some horrible disease. Ugly and ridiculous in itself, and ill-adapted to the growth of plants, the average ‘‘ rockery” is an eyesore. It is rarely productive of any pleasure or satisfaction, even to a mind least exacting. More often than not, it is made in some tree shaded corner, where sun and air, the very essentials to the happiness of rock plants, never penetrate. A few stunted ferns share with a tangle of dusty ivy the melancholy duty of partly screening an ill-considered heap of stones and vitrified brick rubbish. And yet the possession of a few cart-loads of builder’s refuse, clinkers, broken pottery, shells and fragments of statuary, immediately seem to suggest an opportunity for “‘rockery ” making. Small wonder that such spots display nothing of the true charm of a garden, or that they soon come to be regarded as so much waste ground. A I 2 ROCK AND WATER GARDENS As its name suggests, the ‘‘rockery” is a collection of rock fragments and odd pieces of stone, among which a few plants have either been planted or become established. The rock garden is quite different. It is a definite piecing together of natural rock and stone, and is so formed that it shall offer ideal conditions for the growing of Alpines and such plants as occur naturally on mountain sides and at high elevation. In the rock garden the first thought is for the plants that will occupy it: in the “‘rockery ” the disposal of so many loads of débris is the usual aim in view. A rock garden may occupy practically any area of ground, but the idea that the term can only be applied justly to large and important places is certainly erroneous. It is possible to make a charming home for Alpines which will cover only a few square yards of earth, and if the plants and not the stones are the reason for its existence, it will be a garden, and surely one of beauty. It has seemed to me important thus to emphasise the distinction between the rock garden and the ‘‘ rockery.” For one thing it will help to make more clear sugges- tions following; for another, the condemnation of the “‘rockery ” opens out new possibilities to those whose knowledge of Alpine plants is somewhat limited. And, too, it is surely worth while taking pains to understand the needs of the many exquisite families of miniature flowers which deck the mountain slopes, and spring from ledge and crevice, colouring the grey solitudes with wondrous beauty. In all good gardening it is necessary to havea clear idea at the outset what we mean to do. There is too much blind groping after effect, too much carelessness, and the vague supposition that everything will come right in the end. We defy Nature at every turn, and then look to her to conceal and beautify our thoughtless efforts. It is true that garden-making never is and never can be ROCK AND ALPINE GARDENS 3 anything but artificial, and in the designing of rock-work we are making but a feeble imitation of the great forces of Nature. And yet we must certainly study natural effects and natural laws if we are to achieve any measure of success in the growing of Alpine flowers. An entirely erroneous idea exists that the plants usually found on high mountains cannot be grown successfully in lowland gardens. It is not so much the altitude that suits these miniature flowers, but rather the absence of plants of robust habit and coarse growth. ‘There are no trees or shrubs on these wind-swept wastes, no succulent leaf- age, none of those plants which on the plains quickly smother their smaller neighbours out of existence. And so we find an altogether smaller race of plants has taken possession of the barren slopes, secure from molestation, and unmindful of the struggle for existence in which they are always worsted. Here there is ample space for all, sheltered crannies in which Silene and diminutive mosses find a home; sunny corners where the roots of the Alpine Poppy can secure a foothold. Cutting winds and the rigours of winter are hardly felt by these true children of the wilderness, for whose safety the smallest-crevice will suffice, and for whose warmth there is a mantle of snow. Thus a simple lesson is brought home to us. The rock garden is no place for overcrowding, or for the indiscriminate mixing of plants, large and small. Each plant should be carefully tended, and not left to battle for existence with others of stronger habit. Nine rock gardens out of ten are hopelessly overgrown, not so much from the inclusion of too many varieties, but as a result of undue prominence being given to Aubretias, Arabis, and kindred plants. This does not imply that only the smallest flowers should be grown; that would be carrying natural conditions to extreme. The rock garden may contain representatives of most of the Alpine families, from the tiny Androsace, which clings to the rock face 4 ROCK AND WATER GARDENS among the snows, to the Gentians and Harebells which stud the mountain meadows far beneath. But the plants must be grown in colonies, the strong with the strong, the weak with the weak. It is a frequent lament that the smallest rock plants are constantly lost, and to prevent this the rock garden is dotted with unsightly pegs. Seldom it is that unsuitable soil or aspect is the reason for the annual dwindling away of choice seedlings, but very often may the cause be traced to the encroachment of other plants. This crowding-out process may not be visible to the eye—to all appearance the plant is quite isolated. But below the surface, other roots are absorb- ing all the nourishment ; not infrequently the fibres from some neighbouring tree or bush are allowed free access to the best soil in the rock garden. Root restriction in the case of large plants is just as needful as sufficient “elbow room” for the smaller. Most Alpine and rock plants require great depth of soil, a fact which will, perhaps, come as a surprise to many. The professional builders of certain rock gardens entirely overlook this point. Their work is finished when they have reared their cumbersome earth- banks and transported some tons of stone or cement to form miniature precipices, crags, and jagged cliffs. The gardener must attend to the work of planting, and a hopeless task he often finds it. Having no knowledge of the ways of rock plants, no provision has been made for rooting, and the stone ledges are covered with but a few inches of soil. A cup-shaped depression in the surface of a boulder is filled with a pinch of earth, and in this miserable dwelling any small Alpine is considered to be perfectly at home. All this comes of an entire ignorance as to how mountain flowers in their natural haunts live and have their being. Take the case of the tiny Stonecrops, which in the high Alps may be found clinging to the edges of almost perpen- PLANTS IN CREVICES H STEPS WITH SMALL ROUG Photo, by Mrs. Delves Broughton ROCK AND ALPINE GARDENS 5 dicular rock taces. ‘To outward appearance they must exist on such food and moisture as can be obtained from the atmosphere. Yet if we break away pieces of the shaly rock, we shall find smal] white rootlets thrusting themselves into minute crevices through which a drop of water could hardly percolate. Were it possible to extract one of these roots whole, we should probably find that it was some feet in length. So that even in these barren regions, the forces of Nature have been, and are, slowly disintegrating huge rocks, grinding them down into particles from which a plant, but an inch high, may draw life and sustenance. This simple fact should be of most practical assistance to growers of small plants in rock gardens. In itself it explains why, without apparent reason, small Alpines are constantly dying. ‘That they should have been starved for lack of necessary plant food is the last thought to occur; Alpines are credited with extraordinary powers of endurance. Rich soil they certainly do not need; under natural conditions the roots are found in that of the poorest quality, a mixture of sand, coarse grit, and earthy particles. But even in the most unlikely places where Alpines are found, there is soil of some description, and if at any reasonable depth the roots will find it. Otherwise plant life, except of the most restricted nature, would not be found. Unless the designer understands and appreciates the conditions under which rock plants occur, he cannot hope to make a garden home in which these transplanted wildings will flourish and multiply. In the placing of stones forming the rock garden, valuable lessons may be gained from a study of Nature. Not that we want to imitate natural features or erect a miniature Alps in a small garden, but because Nature’s arrangement of rocks is nearly always best suited to the growth of plants. If we notice a particularly vigorous outgrowth of vivid mosses, small plants and ferns, 6 ROCK AND WATER GARDENS jewelling the fissures of a rugged scarp, we shall nearly always find that the rock face is neither perpendicular nor recessed, but that it slopes backward. The advan- tage of this to the plant is obvious. The full exposure to sun and air, and the certainty with which after every shower the rain trickles into the crevices, accounts easily for the increased vegetation. Not so when the rocks overhang. Here there are dark gloomy hollows, which the sun’s rays never pierce; the earth in the fissures is dry and powdery, and in such places a flowering plant is a rarity. A tattered curtain of dark ivy may veil the naked rock, or on a porous limestone green vegetable growths will spread like stains, but of brightness and beauty there is none. Yet in spite of this it is a common thing in rock gardens to see the stones set perpendicularly in the earth, or worse still in such a way that they form a sort of roof to the plants beneath. In the case of elaborate designs in which natural stone is simulated by cement- work, the inclusion of a number of overhanging pin- nacles and awkward masses of stone balanced so that they appear in danger of falling, seems to be an insepar- able feature. Under the idea that Alpines are delicate and need shelter, they are pushed under these rock ledges, quite unmindful of the fact that the soil in such places is as dry as dust, and that they are practically sunless. An ill-considered site frequently militates against the successful culture of rock plants and Alpines. More often than not, a passage between high earth banks is considered to offer ideal natural advantages for the laying out of a rock garden. A moment’s reflection should serve to convince us that mountain plants would be far more at home on ground that is well elevated. Half the rock gardens in the country have been made in cup-shaped hollows and deep cuttings. Hot and airless POLY INOS VSOLT PJAUNUDIS *“SASSITE 0 MOINS Lad plry ay) 9 Poposdey “dOOMLNY NE LYOUH.LAOS NHAUYOS LNOW ROCK AND ALPINE GARDENS | in summer, damp and sunless in winter, these places offer the worst possible opportunities for a race of plants which is accustomed to the fullest exposure. In these misplaced rock gardens we find a sad lack of variety ; the smallest and most interesting plants gradually dis- appear, and a dense growth of robust trailers covers the earth spaces. Besides, if advantage were taken of mounds and natural ridges, much labour and expense would be saved, at any rate in districts where there are rocks and mossy boulders cropping out of the earth. On high ground where the surface soil has been washed away by rains, a minimum of labour will ensure a beautiful rock garden. After all, it is for those who live in favoured localities to make the best use of their advantages ; certainly there is less excuse, in their case, for bad or thoughtless work. The extreme hardiness of most Alpine plants is often overlooked. ‘The smaller and rarer the flower, the less necessity for ‘‘coddling.” It commonly happens that a pocket of rich, loamy soil in a sheltered corner, is regarded as a suitable spot in which to establish some choice seedling: ‘It will give the plant a chance ‘to settle’ comfortably.” But as a matter of fact the seed- ling nearly always dies. If the same plant had been given a fully exposed position in poor gravelly soil, interspersed with small stones, it would probably have survived and thriven. It is astonishing the numbers of Alpines which are perfectly at home along the edges of rough paths, between stones, and in the joints of rude steps. The roots twist among broken stones and push their way through the coarse grit, always finding abundant moisture; surface evaporation being far less under these circumstances than in borders of good soil. Many small plants thrive best when their roots are in dry quarters during the winter: in the chinks of an old wall or in a rock fissure, they escape altogether the 8 ROCK AND WATER GARDENS superabundant moisture of the earth. Although water, either in the shape of a small stream or still pool, often occurs in beautiful rock gardens, it should never be found in places where Alpines are exclusively grown. A lonely tarn may be found on the mountain side, or a tiny spring gush from the rocks, tracing its way like a silver thread to the valley below. But these instances are the exception, not the rule; and in the small space of the Alpine garden, water is destructive to the best effects. In the same way, trees and shrubs, apart from their propensity for impoverishing the soil, are a decided anachronism. All signs of bold vegetation disappear as we ascend the mountain side and approach the home of Gentian and Edelweiss. The rock garden should not be situated near highly cultivated ground, neither should walls or buildings come into the view. It is best approached from the region of woodland or shrubbery, and by walks, the margins of which are left undefined. Occasional mossy boulders, with a bold grouping of Foxgloves and homely plants, will prepare the eye for a change, and incidentally heighten the effect produced. Perhaps the most beautiful way of all in which to gain the garden of Alpines would be across a stretch of turf, through which in places the natural rock appeared. Here we should have patches and drifts of Gentiana acaulis, Muscari, Narcissi and Scilla. Fortunate indeed are those who may attempt something of this kind, happy reminder of those exquisite gardens of Nature, the upland pastures of the Tyrol. PLOZUINOS “SOL PIIYUSUBIS SASSI’ JO UOISSIMLLIE PULY 34) KG PIINPOAPIY (MGA MHHLONV) GOOMINVYd ‘NEGUVO LNOW CHAPTER II ROCK GARDEN CONSTRUCTION THE actual construction of the rock garden demands more than ordinary thought and care. So many miser- able failures are everywhere apparent that we may at least know what to avoid. From the small clinker built mounds, hideously studded with shells, which may be seen in those piteous little gardens of the slums, to the vast heaps of vitrified rubbish, which in certain public parks pass for rock gardens, there is a lesson to be learned from all. If this is the proper way to build a home for Alpine and rock plants, why is it that in such places the plants are so unhealthy? Are there not a thousand beautiful flowers from the mountains which crave admit- tance into our rock gardens? Why, then, the monotony of these mounds and banks of slag and scoriz, on which only dusty Ivy and rampant Vinca seem to thrive? It is well known that quite half of those who thrust pieces of stone into the earth, in the belief that they are building rock gardens, have no knowledge of Alpine plants and their ways. They dot their earth mounds with impossible pinnacles and piled up pieces of rock, placing fantastic effect in the forefront of their endeavour. When finished, their ‘‘ rockery” is about as well adapted as a home for plants as it would be to serve as a break- water. The position of the rock garden will necessarily be determined by special circumstances, but there are certain rules which hold good in all cases. In the first place, 9 ROCK GARDEN CONSTRUCTION 11 Earth ridges, through which weathered rocks thrust their naked shoulders, as on the cleaves of Dartmoor: narrow defiles, pierced by the rushing streams of the smaller Derbyshire dales—these are suggestive examples of Nature’s rock gardens. Nothing looks more pointless than a circular mound of earth and stones raised on perfectly level ground, or the thrusting of a bristling rock promontory across the smooth expanse of a lawn. As a connecting link between two distinct parts of the property, the rock garden fulfils an admirable purpose, and in this case, it matters little whether the way lies through a sunken passage or across sharply rising ground, necessitating the use of rough steps cut in the side of the hill. In such places an entire change of design is demanded, and the use of rockwork appears perfectly natural. ‘*Rockeries” are put up in the most absurd situations— beneath trees, even encircling the trunks; against walls of houses, and in the centre of gravel paths, where they look as though they had been shot bodily out of a cart. It is time that we ceased to employ a beautiful race of plants for association with such contemptible efforts, and bestowed on the growing of Alpines the same rational considerations that are deemed necessary for the culture of vegetables. When a pathway is cut through a high bank, as is often necessary in hill gardens, the steep sides may be prepared for planting by the use of stones to form rough walling. Many Alpines succeed better on these almost perpendicular faces than on level ground, and the walls are so constructed that they show no trace of mason’s work, but resemble rather the sheer drop of a miniature cliff. Raised banks between two sections of the garden, natural knolls and wild craggy ground covered with furze and heather, suggest themselves as other spots offering inducements for conversion into rock gardens. 12 ROCK AND WATER GARDENS Where natural rock stratum exists a few inches below the soil, it will always be better to make the rock garden by excavation rather than by the addition of fresh stone work. The practice of employing artificial stone sub- stitutes, or even carted stone, when already there is a natural outcropping of rock in the ground, is in- defensible. In such cases the difference between the real and the apparent is bound to be strongly marked. Much of the artificial rockwork now so common in both public and private gardens is a poor enough imitation of the real thing. The fault lies not so much in the material itself, as in the manner in which it is employed. The ease with which it can be worked, and its low cost, considering the strength and solidity of its appearance, has led to a new form of desecration in the gardens of the wealthy. I have seen an example of this recently, and can only regret that the owner of that most precious heritage, an old-fashioned English garden, should be so misled as to convert a sunken court into an Alpine peepshow, which might well serve as a sixpenny attraction at Earl’s Court. Until the advent of this pernicious stone work, nothing could have been more beautiful than this sunken lawn with its weathered sun dial, and terraced borders of herbaceous flowers, completely encircling it like the holiday throng at a Grecian amphitheatre. In the time of roses one felt that here indeed pulsed the heart of the English garden. But now all is changed. The turf and roses are swept away, the sundial no longer tells the summer hours. The place is surrounded by an absurd range of beetling crags and frowning cliffs; the ground is strewn with tufa boulders. Small paths and rocky steps suggest a maze, and horresco referens, this ‘‘garden” is approached by rockwork tunnels, in which there is sufficient light to reveal rows of artificial stalactites ! If natural stone is unobtainable in the neighbourhood, ROCK GARDEN CONSTRUCTION 13 the use of the artificial substitute is permissible, but only in moderation. There are men quite capable of imitating very closely the appearance of simple rock forms, or indicating the strata lines in larger exposures. But it must be clearly understood that the employment of such material is only justified when it enables plants to be grown to greater advantage; the thoughtless plastering of a large area of ground with lumps of cement is a hindrance rather than encouragement to the formation of a good Alpine garden. Whilst so many rock plants will thrive on any well-exposed bank, or even level ground, the use of stones cannot be regarded as an absolute necessity. Therefore, unless they are disposed in ‘the best possible manner, it will be better to do without them altogether. When starting the actual work of rock-garden con- struction, one thought must be kept prominently in view—the requirements of plant life take precedence over considerations of the picturesque. For this reason, it is the gardener, not the builder, who should arrange the disposition of the rocks. The latter’s aims are fantastic, and he wishes his rockwork to look orna- mental, even before a single plant has been established. Before anything, the rock garden is a home for plants, and the beauty afforded by the stones themselves, though not inconsiderable, is quite secondary. Granite and limestone may be deeply interesting to the geologist, but they are as nothing compared with the direct appeal of the living plants. Elevation in rock gardens should always be obtained by masses of earth, and not by stones piled one above the other, with soil in the crevices. The foundation of large banks may consist of brick ends, builders’ rubbish, and any convenient material, but above this should be soil to the depth of at least two feet. Too often we see flat rocks laid so as to form a series 14. ROCK AND WATER GARDENS of ledges; or pinnacles in which each stone is carefully balanced on its predecessor, much after the fashion of a child’s erection of wooden bricks. Handfuls of soil are crammed into any convenient crevice, and in such unpromising quarters plants are expected to grow. Naturally, as soon as the roots have pushed their way through the ball of soil, they are in a barren air- chamber, and during a dry summer half of them perish. In the well-built rock garden the soil is rammed firmly home, aad no vacuum exists between adjacent stones. Rocks which are hollowed out on the under side must be sunk into loose soil, so that the cavity is completely filled. Unless the work is made firm in all its stages, the effect of frost and heavy rain will be to cause soil subsidence, leaving innumerable air spaces. At this stage it is helpful to study rocks in their natural positions. A tract of English moorland offers a striking object lesson in this respect. On level ground, smooth rocks, usually of fair size and round in shape, rise a few inches above the ling and heather. Occasion- ally we come upon a slight knoll or ridge, from which a cluster of lichen-stained rocks thrust themselves boldly. The higher the ground, the more rocks, and vice versd. The fact is one which should be remembered in garden- making of this description. Always use the smooth flat stones for the lower levels, and be content with quite a few: higher up the bank the plants will be smaller and the boulders more conspicuous, whilst quite at the top tufts of diminutive Saxifrage and Androsace will cling to the sides of the roughest and most weathered rocks. This is not an attempt to slavishly imitate Nature’s methods, but it is adopted because in no other way do the various families of Alpine plants appear to so great advantage. Stones should be laid in the earth with their broadest sides downwards ; the bases should also be sunk in the AMSVIUOT "Uv go) 7 WMLISAHAT UILDAD uk LE WOATTIOSINIVWAD WONMHdSOHLIT ROCK GARDEN CONSTRUCTION 15 soil. The practice of thrusting pointed fragments of rock into the ground, so that they resemble rows of jagged teeth, is particularly unfortunate. Lines of natural stratification should be simulated where possible, as this produces a more restful and coherent effect than aimless dotting. If the stones are of small size, and the rock garden slopes abruptly, it will be necessary to build an occa- sional course of dry-walling, otherwise the earth will slip forward after heavy rain. The walling must be built very carefully, as it is important that all trace of builder’s work shall be concealed. Choosing the largest stones available, a single course should be laid somewhere about the ground level. The earth must be well rammed, and the spaces between adjacent stones filled with soil. A thick layer of soil is now placed above the stones, in the same way that mortar is spread between lines of bricks. A second course of stones is now put into position, no idea of uniformity in size being entertained. The dry-walling is carried up as far as necessary ; in the case of almost perpendicular slopes, it will be convenient to make a series of ledges, as these permit of freer planting, and serve to break the monotony. When setting the stones, it is desirable that each should be placed so that it tilts slightly backwards, in other words, the front faces are not perpendicular. Not only does this serve to strengthen the wall, but the rain, collecting in tiny runnels, soaks into the earth crevices and refreshes the plants. This rule holds good as regards the disposition of all stones and rocks in the Alpine garden. Shelter is not needed for the majority of such plants, and the ‘‘ penthouse” method of placing rocks, simply produces dry pockets of soil, in which plants struggle vainly for existence. These sections of dry-walling, which are necessary in 16 ROCK AND WATER GARDENS nearly all rock gardens formed on banks, require to be closely planted. The joints and seams between the stones should be completely hidden by Saxifrages, Ferns, Alpine Primulas and various Sedums. Then if the stones have been laid so that they simulate the lines of natural strata, the idea of a wall will give place toa solid, unbroken rock face, in the fissures of which various small plants have established themselves. When build- ing, it is convenient to lay a wooden spline vertically against the front face of the rock wall from time to time: it will then be easy to ascertain if the centre stones are in a line with the rest, or are too much advanced. The latter is a serious error in rock build- ing, as sooner or later it leads to the bursting outward of the whole structure and the loss of many valuable plants. Apart from considerations of economy, local stone should always be used, as being most likely to harmon- ise with the character of the surrounding vegetation. Sandstone blocks are extremely useful, this material having the additional advantage of weathering to a picturesque shade. Limestone is also good; but slaty, crumbling material is of little value, as it soon succumbs to the disintegrating influence of the atmosphere. On no account should gnarled tree roots, broken stumps or woodwork of any description be included in the rock garden, a restriction which, needless to say, includes all such anachronisms as fragments of pottery, and general débris from the stone mason’s yard. The paths in the rock garden should be of the simplest description. They need never be of greater width than will permit of two persons walking abreast, whilst the smaller back paths should be capable of admitting bat one. A good effect will be obtained by sinking irregular stone slabs at intervals, much in the way that the native rock appears along the foot-worn track on mountain side ROCK G. ROCK GARDEN CONSTRUCTION 17 or cliff path. Flat stones by the path edge, with an occasional rock jutting out from the garden slopes, will help to disperse any appearance of formality. Coarse grey gravel and small stones will form the best surface, and provide a dry, clean footway in all weathers. There are many small plants which establish themselves readily among the edging stones and at the sides of the slabs in the pathway itself. Such are the Woodsias, Asplenium and other Alpine ferns, the creeping Sandwort (Arenaria) and the little violet-flowered Wall Erinus (E. Alpinus). Herein lies the beauty of the rock garden, for even as we walk there are flowers crowding the pathway; space is never wasted, there is always some tiny plant willing to occupy the smallest crevice. Rough steps connecting the different levels add much to the picturesque appearance of larger rock gardens. They should be quite informal, and if carefully made will look as though they had been roughly hewn out of the living rock. A long narrow stone slab should be fitted to the front edge of each step, or if this cannot be managed, two or even three smaller pieces connected by sunken cement joints. The cement will afterwards be concealed by small plants and mosses, which may be naturalised by the scattering of a few seeds in a pinch of soil. It is not necessary to pave the tread of the steps, but a few pieces of flat stone may be inserted here and there. For the rest, they may be made firm and level with earth and coarse gravel. In a short time the plants bordering the steps will throw out creeping stolons, draping the sides; dwarf Campanulas will thrive in the joints, and in the corners, safe from the foot of the careless, Rockfoils and Stonecrops will thrust forth their tiny blossoms. CHAPTER III THE GARDEN OF ALPINES In the true Alpine garden will be found only such plants as are indigenous to the Alps. The mixed flora of the rock garden, containing as it does plants from many different sources, here gives place to that of a definite character. This does not imply that our choice is unduly restricted, or that Alpine gardens must be of necessity monotonous. Only in the very largest places could anything like the full number of available plants be included. As for variety, it is endless — evergreen shrubs, exquisite miniatures of lowland kinds, brilliant mosses, lilies, dwarf trailing plants, orchids and ferns, to mention but a few of the types of Alpine plant life which are perfectly at home in English gardens. To know this charming race of plants is to wish their further acquaintance, and when once they have been seen in their native haunts, the desire to grow at least a few of them is inevitable. Unfortunately, though there are many large and im- portant collections of Alpines, there are but few Alpine gardens. We hear of ‘ collections” numbering so many distinct varieties; one has a plant which another has not; a difficult kind has been coaxed into flower, in another garden it has failed altogether. There is something almost pathetic in the appearance of these Alpine show- places. Single plants dotted here and there, pegs and labels, more obtrusive than the flowers themselves, bell-jars and cover glasses to nurture the weaklings— 18 4 g $ 4 THE GARDEN OF ALPINES 19 the whole place looks like a botanical hospital. No general effect is attempted; of unity and purpose there is no sign. When the true ideal of the garden is con- sidered, how puny and pitiful this becomes. With these same materials, or half of them, beautiful pictures might be evolved. Brave masses of colour, stones and rocks matted with jewelled mosses, drifts of snowy Saxifrage, carpets of azure Gentian, a gleam of silver and gold from clumps of Alpine Ranunculus, the deep green of fern and the cobweb grey of Edelweiss. The Alpine garden should be situated on the highest ground available, in fact the more exposed the site the better. The summit of a rocky knoll, or the sides of an earth ridge will generally ensure abundant sunshine for the plants. But little rockwork is needed : in Devonshire, Cornwall and other places where the geological formation tends to produce natural rock features, no artificial work should be attempted. In other districts, quite a large garden may be laid out with the aid of a few cart-loads of rough boulders, but small stones should be mixed with the soil in order to secure free drainage and retain moisture. Alpines, being of small, compact habit, demand restrained treatment in their surroundings. Besides, the use of comparatively few stones permits of larger grouping and bolder masses of colour in the earth spaces, than would be possible if a few chinks and corners among piled up rocks were the only positions available for the plants. So many Alpine gardens are all rocks and no flowers; the former thrust themselves on our notice, for the latter we must search. A common cause of failure in the cultivation of Alpines, is the unsuitable character of the soil to the varieties chosen. Few classes of plants are more exacting in this respect. It is true that certain kinds will accommodate themselves to varying conditions, and make a brave show even under adverse circumstance. But it is never wise 20 ROCK AND WATER GARDENS to depend too much upon suspected adaptability: not infrequently it fails altogether. The geological formation of the Alps includes certain well-defined classes of soil, with a flora peculiar to each. On limestone soils the beautiful Pasque-flower (Anemone Pulsatilla) is invariably content, its violet flowers scattered over the grassy hill- sides in early spring; on ordinary garden loam it frequently fails altogether. Rhododendron Chamacistus, though strictly speaking a native of the Tyrol, is another chalk-loving plant, whereas R. ferrugineum prefers a granite soil. Among the large family of Alpine Gentians, such varieties as angustifolia and Clusii are always best on limestone, whilst on the granite soil their place is taken by Pyrenaica and Kochiana. Having regard therefore to the welfare of plants in the Alpine garden, care should be taken to make the choice of varieties entirely subservient to the class of soil with which we are dealing. Except in very large gardens it is really unnecessary to provide special soil, that is supposing that a garden picture and not a botanical collection is the object in view. There are sufficient plants peculiar either to the granitic or calcareous formation for us to make a garden of either. The gardener who grows plants for their beauty and not for their rarity realises that he can do better by keeping to varieties that suit his soil, than by adapting the soil to accommodate unwilling aliens. In a garden of any size an endeavour should certainly be made to provide an ideal home by means of grassy banks or an approach of fine turf for some of the beautiful flowers of the Alpine meadows. Naturalised in this way they will appear to greater advantage and flower more profusely than in the bare earth spaces among the rocks. In close grass Anemone Pulsatilla is at its best, and in the same place the lovely Alpine Primula (P. Auricula), quite distinct from the florist’s varieties, ros., South poss Stanfield By YS Messrs THE GARDEN OF ALPINES 21 may find a home. The Glacier Pink (D. neglectus), with its tufts of grass-like foliage and clusters of rosy flowers, is another good plant for naturalising. From the pasture lands of the Austrian Alps comes a charming Harebell, (C. pulla), a true gem for the grass. Among the Gentians is the May-flowering kind (Alpina) and the larger Willow Gentian (G. asclepiadea), the latter, how- ever, more suited to positions among coarse grass than in the section devoted to the smallest plants. The Vernal Gentian (G. verna), common on English hillsides as well as in the Alps, prefers limestone, and is never so happy as when exposed to the fullest sunshine, in a cool, moist soil. Where the rocks meet the grass a few patches of the Alpine Heath (Erica carnea) will mark a change in the planting: in early spring the rosy flowers are particularly welcome. Ranunculus aconitifolius, of which our Fair Maids of France is the double form, is one of the best Alpines for naturalising, and is especially free flowering. Finally there are the Alpine violets, which carpet the mountain meadows with a filmy veil of blue. The Spurred Violet (V. calcarata) and the little T'wo-flowered Yellow Violet (V. biflora), are among the brightest and best flowers to grow in the grass near the garden of Alpines. All the above may be naturalised in close turf, and with occasional division and replanting will continue to increase in size and beauty every year. Naturally these small Alpines are not suited to coarse pasturage or for association with the tall growing grasses which thrive in waste places. On the poor limestone soil which best suits them, only the smallest and poorest grasses wil] be found. Such kinds as the Sheep’s Fescue (Festuca ovina), with wiry, setaceous leaves will form an excellent carpet without choking the Alpines out of existence. Higher up the mountain sides where the meadow land gives place to sparse tufts of dry bents and wiry grasses, 22 ROCK AND WATER GARDENS the character of the Alpine plants changes. Here the children of the highlands and the lowlands meet. As yet, we are below the line of snow and glacier, conse- quently the flowers are not yet dwarfed beyond the limits necessitated by ordinary full exposure. Blue is a colour particularly appropriate, contrasting as it does with grey rock faces and the vivid green of Alpine mosses. The Carpathian Harebell (C. carpatica) flowers in July and August, its spreading tufts of large cup-shaped blossoms filling a good sized recess. Its relative the Mont Cenis Harebell (C. Cenisia) is much smaller, with bright rosettes of leaves and blue flowers ; it should be grown in the highest positions and in the poorest soil. C. alpina and C. pusilla, the latter best in a moist gritty loam, produce a charming effect when planted in quantity. The Windflowers form a pro- cession of colour throughout the greater part of the year on the hillsides and meadows of Europe. For our Alpine garden we may select Anemone alpina, a large and graceful kind, requiring a deep soil. The creamy yellow variety sulphurea, though not always easy to establish, contrasts very favourably with the rich blues of its relatives. The Common Hepatica (A. Hepatica) blooms in March, and in sheltered places the foliage is evergreen. A. apennina, found also in our own wood- lands, is a delightful little plant. Nearly all the Wind- flowers like a chalky soil. Erinus alpinus, with violet flowers produced in racemes, is suited to small rock chinks and the earth crevices between stones. In a patch of moist peaty soil, if such exist, we may plant the Bavarian Gentian (G. bavarica) with flowers of iridescent blue rising from small tufts of foliage. G. angustifolia, G. pyrenaica, G. Kochiana, stemless with dark blue flowers spotted with green, and G. Clusii, are all hardy perennials, and give those exquisite shades of blue for which the Gentians are famed. FUIRIS (Z PU//L.1) ox CLUMP OF DWAR Photo. by Mr. Ch THE GARDEN OF ALPINES 23 The family of Saxifrages includes many varieties which are purely Alpine, in fact the genus is probably more fully represented in the mountain ranges of the Alps than any other. They are of the simplest culture and embrace plants of such varied habit, that a beautiful garden might be made of the Rockfoils alone. The large leathery-leaved kinds should be grown in the lower terraces, the silver-hued and green-tufted varieties in the middle spaces, whilst the tiny moss-like growths of the smallest of the genus, will cling to the joints and crevices of the highest rocks. The Pyramidal Saxifrage (S. Cotyledon) is one of the largest, and is readily increased by offsets from the parent plants. Its large silvery leaf rosettes and spikes of white blossoms contrast vividly with patches of blue flowers. 5S. longifolia is even larger, with grey leaves dotted with white, and large panicles of creamy flowers. In a crevice among the rocks the huge leaf tufts are most striking, and providing the roots can penetrate deeply, it will be quite at home in a perpendicular wall. The plant seeds freely and the stock may be readily increased. §. Aizoon is valuable more for its silvery foliage than for its flowers; S. lantoscana, in the in- crusted-leaves section, has a drooping flower spike with bright clusters of narrow leaves. Of altogether smaller habit is the tiny S. cesia, which at first sight might be taken for a small silvery moss clinging to the surface of weathered boulders. ‘The flowers are white, and the plant though not always easy to establish, usually thrives in sandy soil which is not allowed to become dry in summer. SS. Burseriana is one of the most precious plants in the whole of the Alpine garden. As early as January the silver foliage is flecked with brown buds, each carried on a small red stalk. It does best in a well- drained chalky soil, and soon spreads among the stones. S, aretioides is so diminutive that special care must be 24 ROCK AND WATER GARDENS taken to prevent other plants from overgrowing it; the golden blossoms appear in April above the silver leaf cushions. A moist sandy soil suits it, and propagation is effected by seeds or division. Other good Alpine Saxifrages suitable for various positions are S. diapen- sioides, media, moschata, bryoides and squarrosa. In the arrangement of garden pictures, flower masses must be relieved by the introduction of foliage plants. Fortunately the Alps are by no means lacking in suitable flora for this purpose. Many ferns and small native shrubs are available, and by forming a groundwork for bright colour masses, enable the composition of beautiful pictures. The cool, deep green of the Spleenwort Ferns affords a happy contrast to the rich blues and dead whites of Gentian and Saxifrage. Two good kinds are Asplenium germanicum and A. Selosii. The Shield Ferns(Aspidium), which include also the Polystichum, are many of them perfectly hardy, requiring, however, abundant water during the hot weather. Montanum is a true Swiss variety. Between low masses of rock, small clumps of Woodsia look beautiful, especially when the stones are mantled with Sedums and vivid mosses. A slightly peaty soil suits them best, and they require plenty of water. W. hyperborea and W. ilvensis are especially suitable. In shady corners where the drainage is perfect the Bladder Ferns (Cystopteris) soon make themselves at home. C-. alpina, one of the smallest, is also one of the best. Lomaria Spicant and the hardy Cheilanthes are other precious ferns for the garden of Alpines. Though none will deny the beauty and diversity of the plant families which make the Swiss pastures and lower Alps veritable gardens of Nature, yet the true charm of Alpine flowers is only felt when we ascend to the region of ice and snow. Here at last we realise ‘the powerful grace that lies in herbs,” Dull and unimagina- A ROCK BORDER Photo, by Mrs, Delves Broughton THE GARDEN OF ALPINES as tive must be the mind that is not moved when amidst the savagery of Nature, the chaos of rock and dreary waste of snow, a tiny plant springs forth and bravely fights for life. In lowland pastures it would fail to arouse a moment’s thought, but here, in the stillness of the eternal solitudes, its message of life and hope is trumpet tongued. The thinking mind values flowers no less for their capacity of arousing emotions, than for their gifts of colour and form, and I may be pardoned if, in a book of a practical nature, I claim for the smallest of cultivated plants, a power which is not equalled by the most majestic tree or gorgeous exotic. For this reason, a particular interest attaches to the small mosses and diminutive plants which in the Alpine garden are afforded the highest positions. The smaller varieties of Androsace and Saxifrage, which thrive in the grit-filled clefts beside mountain glaciers, often fail altogether in garden soil. It is ridiculous to speak of such plants as ‘‘ delicate” Alpines, or to infer that our climate is unsuited to their needs. Asa matter of fact, the soil in most Alpine gardens is far too rich, and these plants from the highest regions die from over-nutrition. The earth chinks should be filled with the poorest gravel soil, and with full exposure to sun and free drainage the majority will do well. In town gardens Androsaces are difficult to grow, as their small green leaves soon become coated with soot and dust. They are diminutive plants of the Primrose order, and in their native Alps flower directly the snow has melted. Small fissures in the upper part of the Alpine garden should be prepared for their reception, a mixture of gritty loam and sand, with a small proportion of peat, being packed into the crevices. ‘The plants will never thrive on shallow ledges; the roots should strike downwards for at least a foot. During summer 26 ROCK AND WATER GARDENS drought the small fibres will wrap. themselves around stones and rock fragments, finding abundant moisture in the cool depths. In the granite regions of the higher Alps the following Androsaces are found :—A. glacialis, A. carnea, and A. Vitaliana, the two former rosy, the latter yellow. Chalk loving kinds are A. chamaejasme, pink; A. helvetica, white; A. pubescens, white with yellow eye; and A. villosa, pink. A group of dwarf Campanulas, comprising C. Allioni, cenisia and excisa, will swell the list of miniature plants. C. Allioni forms a close network of succulent roots, the stemless blue flowers being raised on small rosettes of leaves. It is found on granite soil. C. cenisia (Mont Cenis Harebell) is another free rooting kind, with blue flowers and bright leaf rosettes. These Campanulas do well on perpendicular rock faces, clothing the joints with exquisite flower and leaf clusters. A tiny Saxifrage, S. caesia, almost like a silvery moss, is another native of the high Alps. It requires a sandy soil, and must not be allowed to suffer from dryness during the summer. The Cobweb Houseleeks (Sempervivum) demand full exposure to sun; in flat spaces among the small Alpines their quaint silver leaf rosettes and pink flowers are very distinct. To combine with these there are many other families of plants, the Primulas and Gentians, Artemisia and Achillea. MOLE U yy MOEN $A DMD “Sassagy aT PRIN NSLAIW SENG CHAPTER IV THE ROCK GARDEN IN SPRING Wirth the first breath of spring bright patches of colour will fleck the slopes of the rock garden, and with the lengthening days the flowers from mountain and hill clothe themselves in summer garb. Quite early, though the keen winds check all tender vegetation, the Alyssum and Rock Cresses shake out their banners of purple and gold. A little later the Cushion Pinks and snowy Arabis mantle the ledges with rosy blossoms and cascades of virgin white. Now is the rock garden at its brightest and best. After the barren greyness of winter, when the flowers in garden borders have scarcely roused themselves from sleep, here is the fulness of life and colour, the fulfilment of the eternal promise of spring. To which class of spring flora are we most indebted for the freshness and charm of the rock garden at this season? Surely our chief cause of thankfulness is to be found in the myriad bulbous plants, the Alpine Izises, the Fritillaries and Muscari, the Narcissi from mountain pastures, the Snowdrops, Chionodoxa, Snowflakes and Scilla. Ifrock gardens were formed for these flowers alone, they would still be worthy of our care, and in this chapter only bulbous plants will be considered. It will be a good day for English gardens when the practice of growing spring bulbs in ornamental lawn beds is regarded with the same disfavour as parterres of broken brick or the once-belauded carpet bedding. 27 28 ROCK AND WATER GARDENS There is no comparison between the stiff lines of Snowdrops and Crocuses used so frequently as border edgings, and the same flowers grown in drifts and colonies among the stones in the rock garden. There is, too, so much variety among these bulbous plants that they may be used with certainty of success under almost any circumstances. Before the winter snow has disappeared, the narrow leaf spikes of Iris reticulata begin to show above the ground. A small colony of these flowers produces a beautiful effect in the rock garden. “There are several varieties, but none can exceed the gold and violet splendour of the common Netted Iris. I. r. cyanea is a dwarf blue form, and purpurea with rich purple flowers is adapted to warm sheltered corners. Krelagei blooms much earlier than others of the genus, but neither the colouring nor the fragrance are so pronounced as in the type. The Netted Irises are not particular as to soil, but prefer that of a somewhat sandy character. Grown in bold clumps, with a ground- work of small Ferns and Mossy Saxifrages, they are among the best of early bulbs. Another good dwarf Iris is the Armenian variety, J. Bakeriana. It is much like reticulata in colour, but possesses a distinctive charm in its violet-like scent. The Iberian Flag (I. iberica) is worth growing if only for the singular beauty of its flowers; the contrast between the purple-veined falls, with their sheen of gold, and the violet-pencilled standards is very striking. A warm, well-drained soil is necessary, as the rhizomes decay unless they are kept dry during the winter. When planting, the roots should be surrounded with sand. Iris cristata (Crested Iris) is a gem for the rock garden, where it may be grown on sunny ledges with a carpeting of small-leaved Alpines. It is only a few inches high, with broad leaves and pale-blue flowers, Vursery', Clapham, Lancaster SILVER SAXIFRAGES C7) tt the Crav THE ROCK GARDEN IN SPRING 29 pencilled with darker markings. In the border, this exquisite little flag would be lost, but a sunny corner among the rocks offers a charming alternative to growing it in pots, where its beauty is shown to but poor advantage. Quite the best dwarf Iris for colour effect is I. pumila, which, owing to the size of its flowers, forms compact masses of violet or pale blue. It grows about six inches high, and from the sturdy character of its leaf growth, smaller plants are not required to hide the soil. Most of the early flowering bulbs produce but few leaves, and therefore look best rising from sheets of dwarf evergreen foliage. This gives a far better effect than the bare earth; moreover, in the latter case the blossoms are liable to be stained during rainy weather. There are many other Irises for the rock garden, and it is a never-ending pleasure to experiment with new kinds, supplying suitable soil and trying the effect of a few bulbs in sunny corners. In addition to those already mentioned, Korolkowi, rosy-lilac; balkana, claret and white; and Cengialti, light-blue, should be remembered. The Narcissi are another large family of bulbous plants, and to them we owe an everlasting debt of gratitude for many precious garden pictures. The larger kinds should be naturalised in grass, in woodland vistas, and among choice shrubs, but the smallest and daintiest varieties are best in the rock garden. Most of the dwarf Daffodils prefer a slightly peaty soil; all demand good drainage and sharp sand around the bulbs. A light top dressing is an incentive to fine bloom, and the delicate kinds, which are liable to injury from spring storms, should be afforded the warmest and most sheltered situations. The Hooped Petticoat Daffodil (N. Bulbocodium) is found growing wild in many of the southern European 30 ROCK AND WATER GARDENS countries. It cannot be considered a hardy variety, but is worthy of a good position. There are various forms all having rush-like leaves. Conspicuus, with large yellow leaves, is very early, as also is citrinus, the pale sulphur French kind. The White Hoop Petticoat (N. B. monophyllus) is an exquisite variety from Algeria. N. triandrus (Ganymede’s Cup) and its sub-variety albus (Angel’s Tears) are among the daintiest of the race, but must be carefully sheltered from high winds. The Rush Jonquil (N. juncifolius) is sweetly scented and not difficult to establish. Though somewhat expensive, a small clump of the Queen Anne’s Jonquil (N. odorus minor) well repays the outlay ; on warm soils the pale yellow double flowers are very striking. If the rock garden contains a somewhat moist corner, it would be worth an effort to grow the Cyclamen Daffodil (N. cycla- mineus). The flowers are bright golden, the leaves a vivid green. On peaty soils it would almost certainly succeed. Beside the Narcissi with their note of creamy yellow, we may place the Scillas and Muscari, giving us a pro- cession of blues from porcelain to deep indigo. Scillas are of the simplest culture, and when once established merely require an occasional top dressing. The best known and perhaps most beautiful form is the Siberian Scilla (S. sibirica), with flowers a delicate shade of pale blue. It is a vigorous kind, and the clumps should be divided every few years. On a warm, sandy soil it blooms in February. One of the most delightful ways of growing this Scilla is to plant bold colonies near the margins of Alpine shrubs. The sight of the blue drifts of flowers escaping from the shelter of dark foliage, and in small colonies descending the rock slopes, is a spring picture of true charm. Later in the year the Spanish Scilla (S. hispanica) raises its stout racemes of pendent bells. It is a vigorous kind, and is suitable for natural- THE ROCK GARDEN IN SPRING 31 ising in grass and on the outer flanks of the rock garden. The white variety (alba) and rosea, a pink form, are also good. For association with choice Alpines it is a trifle too vigorous. S. bifolia, with deep blue flowers, is the type from which several handsome varieties have been evolved. S. b. taurica, S. b. praecox, flowering very early, and S. b. alba, are all worth growing. The Italian Scilla (S. italica) combines extreme hardiness with brilliant colouring and sweet perfume; in semi-wild places we must not forget the improved forms of the ‘Woodland Bluebell (S. nutans). Deeper shades among the Scilla blues may be provided by patches of Grape Hyacinths (Muscari botryoides), which will answer to the same treatment. Other blue flowers are the Chionodoxas (Glory of the Snow), of which C. Luciliae and C. Sardensis are desir- able. They are at their best after they have had time to become thoroughly established. The Bulbous Fumi- tory (Corydalis bulbosa), with purple blossoms produced in April, may be included in large rock gardens, and in really warm localities the lovely Chilian bulb Teco- phylaea cyanocrocus gives us a shade of blue hardly to be equalled. Finally, there are the Dog’s Tooth Violets (Erythronium), with spotted leaves and single, drooping flowers. E. Dens-canis, the best known of the family, thrives in fairly moist sandy soil, but requires a sunny position. The white, tooth-like bulbs should be planted deeply, and division every few years will increase the stock. ‘This variety is of European origin; others come to us from America. E. giganteum and E. grandiflorum are large, white flowered, and succeed on slightly peaty soil. Blue is a colour which in garden pictures calls for contrast. In the spring rock garden, patches and drifts of Snowdrops and Leucojum should be associated with the Scillas and Muscari. There are many varieties of 32, ROCK AND WATER GARDENS Snowdrops, but we need ask nothing better than Galan- thus Elwesii, with its pure, shapely flowers and bright spikes of green leaves. In close, retentive soils it is disappointing, but is perfectly happy in a mixture of good loam, leaf mould, and sand. Snowdrops should never be grown in open beds, when such ideal positions as shrubbery and woodland, close turf and, above all, the rock garden, are available. The Spring Snowflake (Leucojum vernum) may be regarded as a large and handsome form of the common Snowdrop. It grows well in similar positions, and with the same class of soil. In a shady corner, with peaty soil, a clump of Wood Lilies (Trillium) display their pure white three-petalled blossoms above rich shining leaves. Other small bulbous plants there are in plenty. The Cyclamens, europzum, Atkinsii and Coum; the Spring Star-flowers (Triteleia) and Fritillaries, Anomatheca and the American Cowslip (Dodecatheon). Several of the smaller varieties of Tulips are com- monly recommended as suitable for rock garden planting, such kinds as Greigi, sylvestris and Kaufmanniana especially. To my mind, however, they never look well in such positions. Their stiffness and formality ill accord with the wild freedom of mountain plants, and their blaze of colour, glorious though it be, blinds us to the beauty of many a dainty flower and shrub. The wild Tulips are delightful in woodland clearings, meadow sides and shrubbery margins, and for the florist’s kinds nothing can exceed the suitability and charm of old-world Tulip gardens, in the Dutch style, — a formal arrangement for purely formal flowers. They even look well in borders, so that it seems unreasonable that they should occupy valuable space in the rock garden, which affords a home for many plants that will not thrive elsewhere. The same feeling applies to the dwarf Liliums, LapsvIueny ‘MevygDyy ‘ALISANAT UIAVDLD ID TF VOVUAIXWS VOINOL THE ROCK GARDEN IN SPRING 33 elegans, tenuifolium and others. These noble flowers are so much better suited to border grouping, or the peaty soil among Azaleas and Rhododendrons, that despite the opinions of others, I never commend them for the rock garden. Later in the book suggestions are offered for growing the best varieties of Liliums on the outskirts of the bog garden, probably the ideal place for them. It has seemed best to give some reason for thus excluding these two prominent families of bulbous plants ; otherwise the omission might appear unaccount- able. As it is, few are able to include in their gardens more than a few of the lovely children of mountain and moorland, and to them we look for the happiest effects in the garden of rock plants and Alpines. CHAPTER V ROCK GARDEN PLANTS In the planting of rock gardens, we must endeavour to secure by means of careful selection and judicious grouping, an impression of breadth and boldness in the colour masses. Nothing is more satisfactory when contemplating any form of garden art, than the feeling that the designer has from the beginning worked with the idea of achieving some definite purpose; that with a certain ideal ever before him, labour and thought have been systematically devoted to the fulfilment of such purpose. This is especially so in the case of rock gardens, which are often planted without any con- sideration as to their appearance when completed. New plants are obtained from time to time, and as they are received are set in any positions available, regardless of their suitability or otherwise for association with those already established. Bare places must be filled, but that is no reason why the first seedlings that come to hand should be thrust into them, with the mere object of hiding the soil. Beautiful garden pictures are only possible when each small plant is made to play its part in the building up of a definite scheme, constituting either by its colour, habit or contrasting value, to the improvement and completion of the whole. Too often the rock garden is but a thoughtless jumble of scattered units, of materials which in careful hands would amply suffice to ensure a really satisfactory ensemble. There are hundreds of plants suitable for rock 34 ROCKERY AURICULAS ON Charles Fones Photo, by Mr. ROCK GARDEN PLANTS 35 gardens, but only such as are really desirable should be included. The mere fact of rarity should not influence selection: the commonest and easiest grown flowers are often the most beautiful. Nor should too many varieties be grown. It is better to plant two or three representatives of a family in bold groups, than to obtain perhaps four times the number of different species, with but a single plant of each. Hybrids and sub-varieties are often but inferior reproductions of their types, and it is to be regretted that nurserymen should lavish extravagant praise on high priced novelties, ignoring old established favourites because they happen to be both cheap and plentiful. However, variety must not be sacrificed to an undue spirit of conservatism. There are certain plants which are perfectly easy to grow, and at the same time give beautiful effects. The temptation to overcrowd the garden with these hardy, free-flowering subjects, which make a lavish display in return for a minimum of trouble, is only too prevalent. In this way less adaptable plants are excluded, and a certain sameness and lack of interest ensues in the rock garden picture. For rapidly establishing themselves in cushion-like tufts and mantling the edges of the larger stones, the Rock Cresses (Aubrietia) are unequalled. They will grow in almost any soil, and may be increased by seeds or division. A. purpurea and A. deltoidea are the oldest of the group and have long been favourites in English gardens: A. groeca, lilac-purple, and A. Camp- belli, deep violet-blue, give lighter shades among the purples. Near these, a sheet of snowy Arabis would afford a brilliant contrast, and to complete the picture we would arrange a cluster of golden Alyssum. These three families of rock plants, all perfectly hardy, provide materials for creating one of those bold colour effects, which are often more welcome than subtle harmonies. 36 ROCK AND WATER GARDENS Another good grouping would consist of Iberis semper- virens and the yellow Alpine Wallflower (Cheiranthus alpinus). This combination is particularly beautiful on an almost perpendicular rock face, the deep green and white curtain of Candytuft falling among the golden Wallflowers, which thrive exceedingly in the earth fissures of rock walling. An exquisite picture is achieved by a few plants of Lithospermum prostratum (Gromwell), and a cluster of the Pyramidal Saxifrage (S. Cotyledon). Given a large boulder, rising from an earth ledge, we may plant the former so that it falls, a cascade of gentian blue, into the lap of the silver- leaved Rockfoils. In addition to the beauty of blue and silver, tall pyramids of white Saxifrage flowers will rise in graceful clusters before a curtain of azure. Between scattered clumps of the Blue Winter Wind- flower (A. blanda), drifts of Snowdrops may wander freely; a carpet of the white and silver Saxifraga cesia gives an added beauty to the rosy tufts of the Glacier Pink (D. neglectus). Saponaria ocymoides forms with the Creeping Sandwort (Arenaria) a mist of pink and white over rock ledges and grey stones; the graceful flower sprays of Maiden’s Wreath (Francoa) are seen to greatest advantage when backed by the rich green foliage of Alpine Rhododendrons and other shrubs. It would be easy to suggest further combinations, either for form or colour, but the value of garden books lies more in suggestion than in the laying down of fixed rules. A garden heedlessly planted can never be really beautiful; good pictures require something more than the mere covering of a canvas with splashes of paint. The grouping of plants, so that each individual is of some benefit to its neighbour, is a pleasant task, and calls forth the best instincts of the lover of Nature. Rock plants are so numerous that only the best of the different families can be mentioned. These will suffice POON Mosuyy “Ty 9 ojoys HOVOUdd¥Y SS¥ND HLIA NHAMVS NOON ROCK GARDEN PLANTS 37 for a garden of moderate dimensions; in one of large size it would be better to adopt bolder grouping with the same plants, rather than make additional space an excuse for the inclusion of inferior kinds. Rock Garpen PLANTS Acena. Dwarf plants for carpeting. Only the New Zealand variety (A. microphylla) should be grown, and that for the sake of its crimson spines. Achillea. The best of the rock garden kinds are umbellata, with silver foliage and white flowers, and tomentosa, bright yellow. A fairly dry soil suits them best. Adonis. Pheasant’s Eye. A very precious plant. A. vernalis(Ox-Eye), forms dense clumps of fern-like foliage, from which rise large yellow flowers. It blooms in spring, and is suited to a good loamy soil. Division or seeds. 4isthionema. An Alpine sub-shrub. A. grandiflorum, forms dense spreading masses of foliage, covered with stout racemes of rosy flowers. Owing to its prostrate habit it is useful for mantling the edges of rocks. Well drained loam. Seeds. This is quite one of the loveliest of Alpine plants. Alyssum. Madwort. A charming spring flower, rejoicing in the fullest exposure. A. saxatile (Gold Dust) with its brilliant corymbs, blooms in autumn as well as spring. Androsace. Described elsewhere. The best kinds are: A. carnea, glacialis, and helvetica. Anemone. Wind-flower. A. apennina, A. blanda, A. Pulsatilla. See chapters on Bulbous Plants and Alpines. Antennaria. Cat’s Ear. Dwarf plants, of which A. tomentosa forms a silver carpet of foliage. A. dioica, with pink flowers, is worth growing. Simple culture. 38 ROCK AND WATER GARDENS Anthemis. Rock Camomile. A. Aizoon forms pretty tufts, with daisy-like flowers. Anthericum. St Bruno’s Lily. The lily of the Alpine pastures. A deep, sandy soil suits it, and the roots may be divided in autumn. A carpeting of Saxifrages or other dwarf plants look charming as a groundwork for a clump of St Bruno’s Lily. A. Liliastrum. Arabis. Rock Cress. Well known and invaluable. A. albida (White Rock Cress) and rosea a deep pink form, should be grown. Succeeds in any soil. Arenaria. Sandwort. Beautiful plants, with compact masses of foliage, and myriad blossoms. A. balearica (Creeping Sandwort) and the Mountain kind (A. montana), should be in every rock garden. Seed or division. Armeria. Thrift. Dense tufts of grass-like foliage, with rosy flowers. A. cephalotes (Great Thrift), and A. caespitosa (Tufted Thrift) are suitable for association with tall and dwarf plants respectively. Poor sandy soil. Seed. Aubrietia. Purple Rock Cress. Though common rock plants, they are of the utmost value. A. deltoidea and A. groeca are among the best. Any poor gritty soil will grow Aubrietias, and they are readily increased, either by seeding or division. Bulbocodium. Spring Meadow Saffron. Among the spring flowers in the rock garden, the deep, rosy flowers of B. vernum are very beautiful. Warm, sandy soil. Division of the bulbs. Campanula. Harebell. One of the most beautiful families for the rock garden, The Carpathian Harebell (C. carpatica) bears light-blue flowers at midsummer : C. cespitosa (Tufted Harebell) is excellent for rock steps and the edges of stone flags: the American Hare- bell (C. pulla), a lovely kind, does best in slight peat and sand. Other good varieties are cenisia and garganica, the latter suited to rock ledges, over which its pale-blue SHINIOVAH GdVUD HLM NNVd AYANION ROCK GARDEN PLANTS 39 flower racemes hang in great profusion. Campanulas are so charming that in their case we cannot well have too many species. Cerastium. Mouse-ear Chickweed. Dwarf, silver- leaved Alpines, bearing numerous white flowers from May to July. The variety Biebersteini is easily grown and is one of the best. Cheiranthus. Wallflower. For rock garden grouping, the bright orange variety Marshalli is the finest. The Alpine Wallflower (C. alpinus, syn. Erysimum ochro- leucum) is valuable for the joints of rock walling. The perennial Wallflowers thrive in poor soil and a dry position in winter. Cuttings. Colchicum. Meadow Saffron. Drifts of the rosy flowered C. autumnale look exquisite in the grassy approaches to the rock garden. The leaves die down before the blossoms appear, hence the necessity for a carpeting of grass or dwarf Alpines. They are easily grown, increase freely and brighten the garden at a time when flowers are scarce. Coronilla. Scorpion Senna. ‘Though little grown, this is a desirable plant. C. iberica forms dense tufts of trailing foliage, which in June become studded with vivid yellow blossoms. C. varia, with pink and white flowers, is also good. A fair depth of soil is essential. Dianthus. Pink. This large family includes several species of value. The Cheddar Pink (D. cesius) thrives in gritty crevices between adjacent rocks. On rich soil it soon dies. D. deltoides (Maiden Pink), a charming pink spotted variety, is of particularly easy culture. The Glacier Pink (D. neglectus) thrives in sandy loam, its dwarf tufts of foliage and myriad rosy flowers producing a charming effect on the higher ledges. Dodecatheon. American Cowslip. These plants should be grown in similar positions to the Alpine Primulas, the roots being divided from time to time and replanted in 40 ROCK AND WATER GARDENS sandy loam. D. integrifolium blooms in March, the flowers a purplish-crimson. D. Meadia, with drooping umbels of purple flowers, is another good kind. Draba. Whitlow Grass. Among small mosses and in rock crevices a few plants of D. aizoides, with their brilliant cushions of yellow flowers, are interesting Alpines. Dracocephalum. Dragon’s-head. Easily grown plants of the Sage family. D. grandiflorum is covered in July with dense clusters of rich blue flowers. Division or seed. Erigeron. Fleabane. Though most of the family are border plants, E. alpinum grandiflorum should be grown in the rock garden. ‘The mauve, daisy-like flowers are produced very abundantly in late summer. Well drained loam. EFrinus. Wall Erinus. On bare rocky places the racemes of lilac flowers and tufted foliage of E. alpinus are most welcome. Geranium. Cranesbill. The two rock garden kinds are G. argenteum and G. cinereum. Among the smallest Alpines, the clusters of red Mowers arecharming. Seed. Helianthemum. Sun Rose. There are few more beautiful rock plants than these dwarf trailing shrubs. For mantling sunny ledges they are unequalled. They are quite hardy and succeed in any sandy loam. Froma long list of varieties, we may choose H. pilosum, white: H. grandiflorum, yellow: and H. roseum multiplex, double pink. When in full bloom these flowers are of exquisite beauty. Houstonia. Bluets. A grassy little plant, with numerous dainty blue flowers on slender stems.