Hardy Ornamental Trees and Shrubs - With Chapters on Conifers, Sea-side Planting and Trees for Towns

By W. J. Bean

Contained within this book s a fantastic guide to growing various decorative and ornamental plants that are 'hardy', referring to their ability to resist and survive low temperatures. It includes an extensive descriptive section with detailed instructions and illustrations, as well as a comprehensive guide to growing conifers and more. Contents include: “Hardy Trees and Shrubs”, “Bamboos”, “Propagation”, “The American Garden”, “Descriptive List of Hardy Trees and Shrubs”, “Descriptive List”, “Hardy Conifers”, “The Best Conifers”, “Sea-Side Planting”, “Trees for Chalk Soils”, etc. Many vintage books such as this are increasingly scarce and expensive. It is with this in mind that we are republishing this volume now in an affordable, modern, high-quality edition complete with a specially-commissioned new introduction on the history of gardening.

• Language: English
• Publisher: Camp Press
• Release date: Jan 8, 2021
• ISBN: 9781528763660

Book preview

HARDY ORNAMENTAL TREES AND SHRUBS

I. HARDY TREES AND SHRUBS

The increase in the number of cultivated trees and shrubs during the last few decades has been remarkable. Between four and five thousand species and botanical varieties of hardy trees and shrubs are now in cultivation. They are chiefly natives of North America, Northern Asia, and various parts of Europe, only a small proportion coming from the Southern Hemisphere. There is now at the gardener’s command a wealth of material which, alike in quantity, beauty, and variety, far surpasses that of any previous period. In the selection here made the aim has been to include only the most beautiful and distinctive of those that can be cultivated out-of-doors in these islands. The term hardy as given to any particular plant applies with varying force according to the latitude or locality in which it is grown. As a general rule the number of species which can be grown in the United Kingdom without injury by frost increases as we proceed from north to south and from east to west. There are, however, many exceptions. In the west of Scotland, for instance, there are localities more favourable to the cultivation of exotic trees and shrubs than the midland counties of England are. Situations near the sea are as a rule favourable to tender plants, compared with places beyond its ameliorating influence. Thus, such towns as Scarborough and Cromer on the east coast are warmer in winter than inland towns of the same latitude. Cornwall, being affected on both sides by the sea, is about 10 degrees warmer in winter than the London district; so that many plants are grown out-of-doors there which at Kew require the protection of a greenhouse.

In the following pages many species are mentioned that will only bear the winters of the south and south-western counties of England and Ireland. Plants from New Zealand and South America belong, with some exceptions, to this category, and the same may be said of those that have been introduced from the southern portions of Japan and China. In each case this fact is noted. Where no allusion is made to the matter they may be considered as hardy in all but the most inclement parts of the kingdom. In connection with this question of hardiness it may be worth while to remind those who are desirous of making fresh additions to their collections of shrubs, that the capability of withstanding severe winters in the case of many species increases as they become older. Whilst young plants under three years old will be killed off wholesale, others that have reached the adult stage will pass through the same degree of cold quite unaffected. In making trials of doubtful species, therefore, healthy strong specimens should, if possible, be secured, or in the case of young plants protection afforded for a few winters.

Before planting new gardens it is advisable to ascertain what trees and shrubs thrive best in the neighbourhood, or where similar conditions as to soil, moisture, exposure, and altitude obtain. Many species that fail through starting too early in spring when grown in warm, humid situations, will succeed in exposed or elevated positions, where the wood becomes better ripened and a later start is made. In many places the subject of shelter or nurse trees will have to be considered, especially where there is exposure to the north and east. With many shrubs, more particularly tender evergreens, the fierce, biting winds from those quarters do infinitely more damage than merely low temperatures, provided the air is still. The hardiest evergreens are best for purposes of shelter, and such trees as the Holly, Austrian Pine, and Spruce may be associated with Larch, or where an immediate effect is desired, with the quick-growing Poplars. Numerous other deciduous trees may be used, such as the Hornbeam, Sycamore, Beech, and Lime. Such evergreen trees as the Yew or Holm Oak are of great value as screens, but they are slow-growing. In chalky districts many Conifers succeed; on the other hand, Rhododendrons, Heaths, and other Ericaceæ as a rule refuse to grow in soil permeated by lime; in such districts specially-prepared soil has to be provided. The majority of hardy trees and shrubs thrive best in deep, moist soil, but some are much better adapted to poor, light soils than others. Some of the Cytisuses and Genistas, for example, make large bushes and flower with greater freedom in poor soil than when more liberal treatment is afforded. For planting near water the following may be mentioned: Willows, Alders, Poplars, the bald Cypress, Bamboos, Catalpas, Diervillas, Philadelphus, Lilacs, Sea-Buckthorn, and Sitka Spruce.

Few shrubs will grow under Beech, or in Pine plantations; but the following succeed in the shade, or partial shade, of most other trees, those first mentioned being the best adapted for the purpose: Ivy, Periwinkle, Hypericum calycinum, Yew, Gaultheria Shallon, Ruscus, Box, Snowberry, Aucubas, Hazel, Euonymus radicans, Berberis Aquifolium, Daphne Laureola, Ribes, Elder, Privet, Rhododendron ponticum, Holly, Laurel, and Laurustinus. Two new species of Sarcococca from China, viz. S. humilis and S. ruscifolia, have proved to be very useful for shady places.

For planting in large towns, deciduous trees, such as the Plane, Horse-Chestnut, Lime, Sycamore, and Elm, are among the best of the larger trees; whilst of smaller, flowering kinds, Lilacs, Laburnums, Almonds, and Thorns are recommended. Of evergreens the Hollies, Box, Aucubas, Phillyreas, Holm Oak, Euonymus, and Privets are suitable. Some of the best climbers for towns are the Ivy, Virginian Creeper, Ampelopsis tricuspidata, Wistaria, Forsythia suspensa, Jasminum nudiflorum, Common Jasmine, and Cratœgus pyracantha.

Fig. 20.—Avenue of Deciduous and Coniferous Trees

ARRANGEMENT OF SHRUBS

A few observations may be made on the arrangement of shrubs in borders or beds. Instead of the indiscriminate mixing which is so frequent in gardens, the aim should be to group the plants of the same species, either by themselves, or in association with others whose foliage or habit will enhance their attractions. The beautiful Mezereon, for instance, is more attractive where sufficient plants are brought together to cover a few square yards than when it is dotted about singly; and its beauty at the season of flowering is brought out even more effectively if a dwarf evergreen, like Gaultheria procumbens or Berberis Aquifolium, is planted as a groundwork to supply the foil of dark-green which the Daphne, in its then leafless condition, lacks. The Japanese Witch Hazels (Hamamelis), whose yellow flowers are amongst the earliest harbingers of spring, require a similar accompaniment of dark-green against which the bright yellow flowers may show in vivid contrast. The purple-leaved Prunus Pissardi and the yellow-leaved Mock-Orange, or Cornus alba var. Spathii, make an effective combination. It is not suggested that in small gardens the space at disposal should be occupied by large masses of a few things, and variety sacrificed in order to produce a few broad effects. To one who really loves plants the more species and varieties his garden contains the greater pleasure will it afford him. The idea is, rather, that the shrubbery border is more effective, and the beauty of a plant better shown, when it is represented by a group of specimens than when they are distributed singly.

Fig. 21.—Arundinaria Simoni

In large gardens a feature of great beauty and interest may be made by setting apart a piece of ground in which shrubs, trees, and small plants can be allowed to grow their own way, a kind of wild garden in which the hand of the gardener is not evident. Such a garden is best on the outskirts of the garden proper, forming a connecting link between it and the park or woodland beyond. If possible it should have a varied, undulating surface upon which a few scattered trees are growing; and disposed amongst these, in informal groups, should be masses of free-growing Roses, various species of Rubus, Diervilla, Syringa, Philadelphus, Cotoneaster, Berberis, and numerous other shrubs native and foreign. Groups of large herbaceous plants, Snowdrops, Bluebells, Daffodils, and other bulbs may be used with excellent effect. A few evergreens are needed for winter effect, such as Box, Holly, Laurel, and Rhododendron, allowing them to assume their natural habit. Luxuriance of growth is, of course, a first essential, and this means that the same care in trenching, manuring, &c., is as necessary as in the formation of ordinary borders or beds.

BAMBOOS

These hardy evergreens, of which some forty different kinds are cultivated in Britain, are, with one or two exceptions, natives of China or Japan. They are described under ARUNDINARIA, BAMBUSA, and PHYLLOSTACHYS. The recommendations of these plants are their unrivalled gracefulness, their free and quick growth in favourable situations, and the peculiar quality they possess of retaining their leaves in a healthy green condition all through the winter, even when many other evergreens have put on a dull and sombre hue. Their one drawback is that after a severe winter a large proportion of the foliage turns brown, and the plants are thereby rendered unsightly until May or June. For information as to their culture see under BAMBUSA (p. 47). In no position is the beauty of hardy Bamboos more effectively shown than one near (but not in) water—a position, too, which, in satisfying their great love of moisture, usually induces a most luxuriant growth.

PROPAGATION

This subject is dealt with fully elsewhere. We may, however, point out here that with rare exceptions all trees and shrubs are better on their own roots than when grafted or budded. Grafted plants may have an advantage at the start, but in the long run seedlings and own-rooted plants will overtake them. For instance, Phillyrea decora, grafted on the common Privet, succeeds well enough for two or three years, but after that time it almost invariably becomes sickly. Evergreen Oaks grafted on deciduous ones, and all grafted Conifers, should be avoided. The fine garden varieties of Lilac are frequently grafted on the common form, with the result that, unless a continual look-out is maintained, the named variety ultimately disappears in a forest of suckers. Hardy garden varieties of Rhododendron are usually grafted upon R. ponticum, which proves a suitable stock if kept free from suckers, but if neglected in this respect the scions in time entirely disappear through the suckering of the stocks. In the case of trees, there is always a danger of the stems snapping off through faulty stocks or an imperfect union, which is often also the seat of cankerous, fungus-infested wounds. The safest method of grafting is to work the scion on the root of the stock; this usually prevents the formation of suckers, and has also the great advantage of allowing the scion to root on its own account.

THE AMERICAN GARDEN

This term is usually applied to a piece of ground set apart for plants which enjoy a moist, peaty soil. Many of them are natives of North America, and they have come to be known collectively as American plants. In its geographical application the term is somewhat misleading, numerous shrubs belonging to this group being natives of Japan, Europe, and even of the British Isles. American plants are for the most part included under the two natural orders Ericaceœ and Vacciniacece, and some of the chief genera comprising the group are: Rhododendron, Azalea, Kalmia, Erica, Arbutus, Andromeda, Clethra, Pernettya, Vaccinium, Ledum, Gaultheria, Daboëcia, Arctostaphylos, Pieris, Leucothöe, Lyonia, Zenobia, Menziesia, &c. Their special value lies in their neat dwarf habit, the beauty and profusion of their flowers, and their rich green and mostly persistent foliage. A few, however, like most of the Azaleas, are deciduous.

American plants prefer a moist, cool soil, and generally they dislike lime, so that in many limestone districts it is useless to attempt to grow them unless in specially prepared soil. It is, however, interesting to note that some of the Heath family thrive even better where it is present: Rhododendron hirsutum and Rhodothamnus Chamœcistus are cases in point. Several of the Ericas thrive in chalky districts, such as E. mediterranea and E. cinerea. Recent exploration in Western China has shown that a very great number of Rhododendrons grow there on limestone formations. There are, of course, different kinds of limestone. In the British Isles the commonest form is chalk, and it has not yet been conclusively proved that many species will tolerate this. But whilst this question of lime and Rhododendrons needs further experiment and elucidation, the following species promise well in chalky soils: ambiguum, Augustinii, calophytum, Davidsonianum, rubiginosum, rupicolum, Hanceanum, Wiltonii. Where the natural soil is free from chalk the stronger-growing species may be used in shrubbery borders. The soil most suitable is undoubtedly one of a peaty nature, but many of them may be grown in a loamy soil, if free from chalk and of sufficient depth and body to retain moisture during long spells of dry weather. Rhododendrons, for instance, will sometimes grow in stiff loam.

Where the soil is of a clayey nature it should be trenched to a depth of two feet, and good leaf-soil—and, if practicable, peat—mixed with it so as to render it lighter and more open. Poor, sandy soils should be strengthened and made more retentive of moisture by adding loam, leaf-soil, and peat, and the greater depth to which this is done the better, for the greatest drawback in cultivating American plants on such a soil is its hot, dry state during long spells of heat, which artificial waterings, however copious, can only partially remedy. On the other hand, stagnation at the root is as injurious as the other extreme. In chalky localities, where specially prepared soil has been provided, care should be taken that it is not so placed that water impregnated with lime from the surrounding land will drain into it. For this reason such prepared beds ought to be elevated one foot to two feet above the surrounding area. Rhododendrons and Azaleas are much benefited by an occasional top-dressing of decayed cow-manure and leaf-soil in equal parts.

The best position for American plants is a sheltered hollow or ravine opening to the south or west. Such a position affords abundant scope for varied and informal arrangements, especially if a few other trees and shrubs are introduced, such as Magnolias, Acers, Lilacs, Liquidambars, and the hardiest Bamboos.

DESCRIPTIVE LIST OF HARDY TREES AND SHRUBS

ABELIA.—Dwarf branching shrubs with small opposite leaves, and tubular pink and white flowers. Allied to Diervilla, but less showy. Except in especially favoured localities they are not very hardy. A. floribunda with rosy flowers, and A. triflora with pink ones are sometimes grown on walls. The hardiest is A. grandiflora. Two new species from China are A. longituba and A. Engleriana.

ACANTHOPANAX (including ELEUTHEROCOCCUS).—Deciduous trees or shrubs allied to the ivy and bearing very similar globose clusters of purple-black fruits. Stems often spiny or bristly. Leaves either compound, consisting of three or five leaflets digitately arranged, or deeply lobed. They like a well-drained loamy soil and a sunny position.

A. Henryi.—A bush 6 feet or more high, with stiff bristly branches. Leaflets five, each 3 inches long. Fruits inky black, in clusters 2 inches wide. China, 1901.

A. ricinifolium (Maximowiczii).—A tree sometimes 80 feet high in a wild state. The young trunk and branches are formidably armed with stout spines. Leaves very handsome, 10, sometimes 14 inches wide, deeply five- or seven-lobed. Japan, 1865.

ACER.—Round-headed trees of moderate or large dimensions, with lobed, trifoliolate, or pinnate leaves and small flowers. The Common Maple and Sycamore are familiar examples. Many of the species have brilliantly-coloured foliage in autumn.

A. campestre, Common Maple.—A small tree with corky bark and five-lobed leaves. Will grow under the shade of other trees. Europe.

A. carpinifolium.—A very distinct and striking small tree with leaves almost exactly like those of the Hornbeams, but, of course, not alternate. Japan, 1879.

A. circinatum.—A medium-sized tree with roundish leaves, downy beneath, cut into about seven shallow lobes which acquire a bright-red tint in autumn. North-West America; introduced in 1826.

A. crataegifolium.—One of the remarkable Maples whose younger branches are striped with white lines. Leaves ovate, toothed, but only shallowly lobed. Var. Veitchii has the leaves handsomely blotched with rose-colour and white. Japan, 1879.

A. dasycarpum (A. eriocarpum), Silver Maple.—A very fine ornamental tree, 60 to 100 feet high. Leaves blue-white beneath. North America, 1725.

A. Davidii.—A tree 30 to 50 feet high; younger branches striped with white. Leaves ovate, toothed, up to 7 or 8 inches long, reddish when young. A promising new maple from Central China, 1902.

A. Ginnala.—A dwarf tree of graceful habit. Its prettily-lobed leaves turn a rich red in autumn. Amurland.

A. griseum.—One of the Negundo group, each leaf consisting of three distinct leaflets, turning red and orange-colour in autumn. A tree 40 feet high, with peeling bark orange-brown when newly exposed. Central China, 1901.

A. Henryi.—A tree 30 feet high, leaves trifolio-late, differing from all other Maples of the same group in having entire leaflets. Central China, 1903.

A. japonicum (fig. 22).—A shrub or small tree in the way of A. circinatum. Often confused with A. palmatum, from which it is easily distinguished by its leaves having usually eleven lobes, whereas in A. palmatum there are normally five or seven. Japan.

Fig. 22.—Acer japonicum. (1/3)

A. laetum.—A small tree with smooth, five- or seven-lobed leaves; leafstalk milky when broken; each lobe ends in a long tail-like point. The species is best known in cultivation by the var. rubrum whose young foliage is red. Syn. A. colchicum rubrum. Caucasus, 1846. Var. tricaudatum has three-lobed leaves. Western China, 1901.

A. Lobelii.—A tree 50 to 60 feet high with erect branches and a columnar form. Allied to the Norway Maple but very distinct. Southern Italy, 1683.

A. macrophyllum (fig. 23).—A lofty-growing tree, 50 to 100 feet, with