Alpine or Rock Garden Design

Planting A Rock Garden

If the reader has been able to derive sufficient help and information from the earlier homepage, he/she will naturally be anxious to know how to plant their garden, and the best varieties of plants to use, and as the ultimate result will largely depend on the selection made and whether the plants are judiciously grouped, their choice and arrangement should most carefully be considered. Otherwise the result will be but chaotic and inartistic, no matter how skilfully the garden has been engineered.

How to group plants so as best to show off the beauty of the individual, while at the same time producing the most telling effect in the general scheme is in my opinion one of, if not quite the most difficult branch of rock gardening, while it is also the most important.

It is at times almost impossible to know how best to produce the desired effect ; there are so many points to be considered before the final home for any plant is selected. First arises the question of aspect, whether that chosen will suit it ; then how it will combine in color, habit and time of flowering with its next-door neighbour. One is sometimes almost in despair, for no place seems to answer all requirements, and one is almost induced to follow the slovenly and lazy gardener's motto of "Oh, put it in anywhere." But anywhere is nowhere, and there must be some spot that will suit it best, and that spot should be found, even if it entails a considerable amount of trouble.

I do not profess to be an artist, nor will I attempt to venture into those mystic schemes of color of which one hears so much, but sees so little, except in the cataloges of nurseries. In rock gardening, and in fact -in all kinds of gardening, the best results are frequently obtained by the simplest means. The chief thing to avoid is a confused mixture of many brilliant colours, giving crude contrasts ; at its best it has but a patchy appearance, and does not give that harmony of color which it should be one's object to obtain. And the beauty of the individual plant will suffer no loss from a judicious blending for general effect; rather the contrary, for by a good combination the individual also will be shown at its best.

Before proceeding to discuss further the planting of alpine and rock plants, it would perhaps be as well to explain what is meant by alpine and what by rock plants, lest some confusion should arise, owing to the two names being often used synonymously. Alpines derive their name from their original home-the Alps. Rock plants, which include alpines, are those collected from, all parts of the temperate world, be it mountain or valley, which, so long as they are suitable in habit and height, are used in the rock garden

Henceforth it may be understood for the sake of brevity that in "rock plants," alpines and all suitable varieties are included.

Rock plants, looking at them with a view to grouping in the garden, may be divided into two classes
  1. those which, on account of their freer growth and more generous bloom, can be effectively used for massing; and
  2. those which are grown chiefly on account of their intrinsic beauty, but which, owing to their slower and more diminutive growth, will not, in this country at least, give the same bold dashes of colour.

In the former class may be included such families as the Aubrietias, Rock Roses Arabis, Cerastium, Campanulas, etc.-in fact, most of the commoner plants grown in the rock garden. In the latter class one has such lovely things as Soldanella alpina, the rarer Saxifrages, such as S. diapensioides, caestia, Burseriana, Faldonside etc.) Campanula Zoyzii, Rainera, Edrianthus, Phyteuma comosum, and many others too numerous to mention here all and each lovely in themselves, but whose beauty would be lost if planted beside, say, a yardsquare avalanche of Aubrietia. So it is advisable that these more diminutive treasures be grown in a part of the garden reserved for them alone, and not mixed with the coarser kinds. It is all very well for people to talk about carpeting the ground with Androsace glacialis, Eritrichium nanum, or Campanula Rainera ; it is so in Switzerland, but it cannot be achieved in the British Isles.

Keep all the choicer Saxifrages together, choosing a well-drained spot fully exposed to the sun, with soil containing a good propor-tion of lime-rubbish, sand, and broken stones. I have grown together, and bloomed well, S. diapensioides, Faldonside, caesia, Ferdinandi, Coburgi, Boydii, Burseriana, and others of the choicest kinds, which would have been lost and passed unnoticed if scattered throughout other parts of the garden. There are numbers of other Saxifrages strong-growing and beautiful, such as apiculata, sancta, Wallacei, Rhei, Guilford, and Cotyledon, which will make as much growth in one season as the previous mentioned kinds will in ten. So use these latter in large bold masses for covering your rocks and level spaces.

The following general scheme of planting might well be adopted: -To fall over the rocks bordering the paths mass Aubrietias of all kinds Arabis, Hypericum reptans, Androsace lanuginosa and its variety Leichtlini, Dianthus suavis, Thymes, etc.; while in places where the rocks are but little over the level of the path, tufts of mossy Saxifrages, Campanulas, etc. , may be allowed to spread on to the path. Behind this, which may be called the edging, plant over the rocks the lower-growing kinds and creeping varieties, while on the level spots place such plants as Silene alpestris, Campanula pulla and Gentians., Dianthus, etc., interspersed here and there with plants of a taller - growing habit, so as to avoid a too flat appearance. Behind these again the bolder-growing plants and smaller shrubs or shrubby plants, merging gradually into the shrubs which form the background.

Always endeavour to plant in bold masses. Avoid single specimens dotted here and there.

If the garden is large, one or even two square yards is not too much space to devote to one variety ; but this is not always easy to accomplish. It takes so many plants of one kind to cover the space desired, especially considering how small they usually are when received from nurserymen, and the expense of a large number is often prohibitive. But if only two or three plants can be obtained in the beginning, instead of the dozen or more required, I would still advise assigning the larger space, and in the autumn propagating from one of your own plants. It cannot be expected that the garden will be properly clothed much under four years, unless a very large number of plants are purchased to begin with. And even when this cannot be done, it is still better to a opt the system of massing., for massing is the secret of effect. Though often the individual flowers of rock plants do not possess much intrinsic beauty in themselves, when grown in large quantities they are most effective.

When massing plants, endeavour to vary the shape and outline of each group as much as possible, for otherwise a formal effect will be produced, which is very objectionable. The formation of the round will help in this, to a certain extent at least.

As an example of what can be obtained by this method, imagine a drift of Campanulas stretching half way up the face of the bank, with a tuft of mossy Saxifrages covering the rocks which bound the path, while in another place a cascade of Androsace lanuginosa falls on to a strip of Silene alpestris growing at its foot While again a dazzling patch of Gentiana acaulis is seen extending right up to rocks covered with a snow-white torrent Thymus Serpyllum alba. Many such pictures as these could be suggested did space permit.

Annuals may give a great show of bloom for some months during the summer, and are usually very easy to grow; but they have the great objection that once their bloom is past they die away, leaving an ugly blank in the garden. With the majority of perennial rock plants it is different. They are beautiful even when not in bloom, on account of their foliage and habit of forming compact tufts, which increase year by year, and give that idea of permanence so lacking in annuals. For these reasons I never use annuals of any kind, if I can avoid it, except that dainty little yellow Saxifrage, Cymbalaria, which appeared in my garden of its own accord, and goes on sowing itself from year to year, but never encroaching.

Many varieties of bulbs can be used with delightful effect on the slopes of the rock garden. They have, however, one objection, that they only make a show during the flowering season, which, alas ! is all too short. Once that is over, little else but withered leaves remains. To remedy this defect, put your bulbs under dwarf- and close-growing plants, such as the Thymes, Sedums, mossy Saxifrages, etc. In the spring they will push up through these carpets, have their flowers, and disappear until the following year.

Ferns can also be used with good effect in the shadier and damper parts of the garden. Their lovely green foliage will show off and accentuate the livelier colouring of the flowers.

My reiterated emphatic advice with regard to the scheme of planting is to mass. Mass boldly, covering the rocks and all the surface of the ground. The fully matured rock garden should have no untenanted spot, nor in summer show any bare spaces. Therefore, mass ; but it must be left to individual taste and circumstances to decide how to obtain the best effects from the material at hand.

With regard to what are the best species to plant together, colour and time of flowering will have especially to be considered, provided always that the aspect suits both species equally well.

It is not advisable to devote too large a space to plants of the same flowering season, for though the result during that period may be pleasing, it will be apt to make rather a blot on the general effect when their bloom is over. So I refer to mix the plants in such a way that from April to September there will be no art of the garden quite devoid of bloom, though, as might be expected, the garden will be much gayer at some times of the year than at others.

Another point to look to, and one often rather liable to be forgotten, is that no very strong and rapid-growing plant should ever be put beside one that is of slow growth and delicate habit, or the former will sooner or later smother the latter.

Never plant rubbish. Do not be persuaded by your friends "'just to fill up your garden with anything to make a show the first year." This is the greatest mistake, for you may afterwards have difficulty in getting rid of what you planted merely as a "stop-gap."

A word of warning may not be out of place with regard to very strong and rampant growing plants, especially those that have a creeping rootstock, for great discretion will have to be exercised in planting them owing to the difficulty of removing them when once established behind some large rock. Nothing in the shape of a. rampant grower should be planted in the part of the garden reserved for the choicer kinds. The wild garden is the lace for such dangerous characters, for their encroaching habits will not so much matter there.

I speak from experience. In a weak moment, and I must confess in ignorance of its habit, I planted in one of the choicer parts of my garden a plant of Convolvulus altheeoides, a very attractive plant in itself. In two months it had made wonderful growth, clothing the adjacent rocks with its creeping stems. My suspicions having been aroused, I examined- the ground around, and about 4 feet from the parent plant I found a sucker of it just appearing in the middle of my best plant of Daphne Blagayana . To get there it had to work its way behind a rock weighing about a quarter of a ton. Further investigations showed that it was spreading in all directions, and had reached as far as 5 feet from the original plant, which was hastily banished to the wild garden. All the rockwork had to be taken down in order to thoroughly clean the ground. So that two days' hard work was the result of a thoughtless moment. Let this experience of mine be a warning to the reader on no account to plant anything, except in the wilder parts, that will be likely to take possession of his garden.

Leaving the rock plants, we will now deal with the shrubs, the dwarf-growing kinds, which can be mixed with the plants, or form a connecting link with those of stronger growth which are to make the background of the garden.

Too much care and attention cannot be devoted to the planting of the shrubs, both large and small. On their judicious and skilful arrangement the success of the garden from an artistic point of view will greatly depend.

The modern rock garden is usually a copy, or more often an attempt to copy, some mountain scene on a very reduced scale, and that it is on a very reduced scale is evident from the fact that where in nature we find rocky crags or Cliffs 30 feet or 40 feet high, we, in our puny imitations, have to be content with rocks measuring as many inches. In order, therefore, to carry out this idea correctly, we should use trees and shrubs, proportionate in size to our rocks. Amongst the rocks should be planted dwarf shrubs such as Ledum buxifolia Azalea am6ena or Cistus florentinus, and such miniature trees as the dainty little Pinus sylvestris Beuvronensis, or some Retinospera obtusa pygmaa, pigmy re-productions of those gnarled and aged giants found on the scene we wish to copy.

The secret of a faithful reproduction is proportion. For example, by planting one of these dwarf trees at the foot of some rock., or inserting it in some fissure, such an added value of dignity and height will be imparted that the rock will a ear to be transformed into a rugged cliff. So again, by planting on some height a group of Junipier Sabina, the idea is conveyed of a wind-swept mountain crag. Time will indeed be well spent in working out pictures like this and trying where such as these will look best and most effective. Place a group here or a single specimen there, and study the effect from different points before finally planting. The results that can be obtained are wonderful so long as the sense of proportion is preserved. So also with the dwarf shrubs, though in a somewhat lesser degree, for they are not such faithful copies of their larger prototypes. But with the grouping and arrangement of these dwarf trees and shrubs, the faithful picture ends, for I must confess find it difficult to assimilate a pigmy Scotch fir of say 8 or 10 inches high with a 4 feet specimen bush of Cistus ladanfierus or Olearia Hastii, though it is undeniable that such shrubs are a necessary and attractive adjunct to the rock garden. The only way I can find out of the difficulty of combining dwarf shrubs and trees with those of larger growth, is by planting the latter so far away from the pigmy specimens that they form merely a background.

As it is imperative that this background should be permanent, evergreen shrubs should chiefly be used. But do not for a moment think it is desirable to ignore the deciduous section, containing, as it does, many of the most beautiful of flowering shrubs. These should be so laced that the full value of their beauty when in flower is obtained, while not at other times affecting the permanent scheme.

This may appear to be somewhat contradictory advice, but by judiciously mixing the evergreen with the deciduous, such an effect can be achieved. The advice as regards the massing of the plants a lies also in a certain degree to shrubs for when several of the same species are planted together, the effect is far more striking than when they are grown singly.

Of shrubs suitable for covering the heights and the intermediate space between the rock plants and the larger shrubs, I should advise a selection from the following: -The family of Rhododendron is of chief importance, and varieties suitable for our purpose will be found in such dwarf-habited kinds as ciliatum, hirsutum, ferrugineu, Racemosum, myrtifolium; also Azalea amaena and its varieties the Menziesias, polifolia , polifolia alba, and Bicolor and of the Ledums, Palustris and latfiolium ; while amongst the numerous Cistus, family such varieties as florentinus, formosus, lusitanicus, and Rosmarinifolius will be found most useful. Of the Genistas and Cytisus one cannot go far wrong in selecting the following: Cytisus Ardoini, Kewensis, purpureus, and Purpureus albus, Genista prostrata, saggitalis, and tinctora, fl.pl.

Some of these, such as Cytisus Ardoini and Kewensts, and Genista prostrata, which grow only a few inches high, will creep over a rock, covering it with a compact green cushion, which in summer will be transformed into a sheet of cream or gold.

It is not, however, a good plan to line all the heights with these dwarf shrubs, for that would tend to give a monotonous appearance. Therefore, vary the effect by planting here and there, almost up to the rock plants, a group of the stronger-growing brooms such as Cytisus Praecox and Praecox alba, Carlieri, scoparius, etc.

Shrubs, deciduous and otherwise, suitable for massing in the background are legion, and every year new varieties are being introduced - some hardy, and others only half hardy.

Therefore, to a certain extent the selection made will depend on the climate. For instance, in my garden, I can grow without the least protection during the winter such shrubs as Metrosideros floribunda, Carpenteria Californica, Cistus formosus, Myrtus apiculata, Grevillea rosmarini-folia, and many others which are considered only half hardy but all people are not so fortunate.

Unfortunately, Rhododendrons will not grow everywhere for they belong to that group of shrubs which includes so many lovely and rare species, namely, the peat-lovers, on, as they should more accurately be called, the lime-haters. I have a little lime in the soil of my garden, and Rhododendrons, though they live, will not thrive as I should wish them to ; otherwise I would grow them as freely as I would advise all others to do, whose soil is more suitable.

 



Free Garden Catalog



 

gardeninggardening